Combination therapies for treatment of breast cancer

Abstract

This invention provides a combination therapy comprising a PI3K inhibitor (e.g., epfuliximab), a CDK4 / 6 inhibitor (e.g., palbociclib), and fulvestrant; and a method for treating patients (preferably those with PIC3CA mutations) with hormone receptor-positive and HER2-negative (HR+ / HER2-) locally advanced or metastatic breast cancer, the method comprising administering a therapeutically effective amount of epfuliximab or a pharmaceutically acceptable salt thereof, a CDK4 / 6 inhibitor (e.g., palbociclib), and fulvestrant or letrozole.

Description

[Technical Field]

[0001] This invention generally relates to the treatment of PIK3CA-mutated cancer patients for the treatment of breast cancer by administering the PI3K inhibitor sefliximab (also known as GDC-0077) in combination with CDK4 / 6 inhibitors and endocrine therapy. [Previous Technology]

[0002] Globally, breast cancer is the second most common invasive malignancy and the leading cause of cancer-related death in women, with a 5-year survival rate of approximately 15% after a metastatic diagnosis.

[0003] Phosphopeptide inositol 3-kinase (PI3K) is a lipid kinase that, upon activation by growth factor receptors and integrins, regulates cell proliferation, survival, and migration. PI3K catalyzes the phosphorylation of phosphatidylinositol 4,5-bisphosphate (PIP2) to generate phosphatidylinositol-3,4,5-triphosphate (PIP3), which is the second messenger involved in the phosphorylation of other components in the AKT and AKT / mTOR pathways. Up to 70% of breast cancers have some form of molecular aberration in the PI3K / AKT / mTOR pathway. Activating mutations in PIK3CA, which encodes the PI3K p110α subunit, are very common in breast cancer and solid malignancies.

[0004] Accordingly, there is an urgent need for active agents for the treatment of hormone receptor-positive and HER2-negative (HR+ / HER2-) locally advanced or metastatic breast cancer. [Summary of the Invention]

[0005] This disclosure provides a combination therapy comprising a PI3K inhibitor (e.g., GDC-0077), a CDK4 / 6 inhibitor (e.g., palbociclib, ribociclib, or abeciclib), and an endocrine therapy (e.g., fulvestrant or letrozole) for the treatment of breast cancer.

[0006] One aspect of this disclosure provides a combination therapy comprising a PI3K inhibitor (e.g., GDC-0077), a CDK4 / 6 inhibitor (e.g., palbociclib, ribociclib, or abeciclib), and fulvestrant for the treatment of breast cancer.

[0007] Another aspect of this disclosure provides a combination therapy comprising a PI3K inhibitor (e.g., GDC-0077), a CDK4 / 6 inhibitor (e.g., palbociclib, ribociclib, or abeciclib), and letrozole for the treatment of breast cancer.

[0008] This disclosure further provides a method for treating patients with hormone receptor-positive and HER2-negative (HR+ / HER2-) locally advanced or metastatic breast cancer, the method comprising administering a therapeutically effective amount of GDC-0077 or a pharmaceutically acceptable salt thereof, a CDK4 / 6 inhibitor (e.g., palbociclib, ribociclib, or abeciclib), and endocrine therapy (e.g., fulvestrant or letrozole).

[0009] In one embodiment, this disclosure provides a method for treating hormone receptor-positive and HER2-negative (HR / +HER2-) locally advanced or metastatic breast cancer in a patient, the method comprising administering a therapeutically effective amount of GDC-0077 or a pharmaceutically acceptable salt thereof, palbociclib, and fulvestrant.

[0010] In another embodiment, this disclosure provides a method for treating hormone receptor-positive and HER2-negative (HR+ / HER2-) locally advanced or metastatic breast cancer in a patient, the method comprising administering a therapeutically effective amount of GDC-0077 or a pharmaceutically acceptable salt thereof, palbociclib, and letrozole.

[0011] In some embodiments, the patient has PIK3CA mutation, hormone receptor positive, Her2 negative, locally advanced or metastatic breast cancer.

[0012] Also provided is a combination for treating hormone receptor-positive and HER2-negative (HR+ / HER2-) locally advanced or metastatic breast cancer, wherein the combination comprises administration of GDC-0077 or a pharmaceutically acceptable salt thereof, a CDK4 / 6 inhibitor (e.g., palbociclib, ribociclib, or abeciclib), and endocrine therapy (e.g., fulvestrant or letrozole).

[0013] Also provided is the use of a combination of medicines for treating hormone receptor-positive and HER2-negative (HR+ / HER2-) locally advanced or metastatic breast cancer, wherein the combination comprises administration of GDC-0077 or a pharmaceutically acceptable salt thereof, a CDK4 / 6 inhibitor (e.g., palbociclib, ribociclib, or abeciclib), and endocrine therapy (e.g., fulvestrant or letrozole).

[0014] In some embodiments, the hormone receptor-positive, Her2-negative, locally advanced or metastatic breast cancer is a PIK3CA mutation or has one or more PIK3CA mutations.

[0015] In some embodiments, GDC-0077 is administered at a daily dose of 9 mg.

[0016] In some embodiments, a method of treating a patient with hormone receptor-positive and HER2-negative locally advanced or metastatic breast cancer is provided, the method comprising administering a combination therapy to the patient comprising GDC-0077, palbociclib, and fulvestrant, wherein the combination therapy is administered over a 28-day cycle.

[0017] In some embodiments, a method of treating a patient with PIK3CA-mutated, hormone receptor-positive, and HER2-negative locally advanced or metastatic breast cancer is provided, the method comprising administering a combination therapy to the patient, the combination therapy comprising a dosing regimen comprising: a. administering GDC-0077 via QD on days 1 to 28 of the first 28-day cycle; b. administering palbociclib via QD on days 1 to 21 of the first 28-day cycle; and c. administering fulvestrant on days 1 and 15 of the first 28-day cycle.

[0018] In some of these embodiments, the method further includes one or more additional 28-day cycles, comprising: a. administering GDC-0077 on days 1 to 28 of each additional 28-day cycle; b. administering palbociclib on days 1 to 21 of each additional 28-day cycle; and c. administering fulvestrant on day 1 of each additional 28-day cycle (or approximately once every 4 weeks).

[0019] Also provided is a combination for treating PIK3CA-mutated, hormone receptor-positive and HER2-negative locally advanced or metastatic breast cancer, wherein the combination comprises GDC-0077, palbociclib and fulvestrant, and wherein the combination is administered over a 28-day cycle.

[0020] A combination therapy for treating PIK3CA-mutated, hormone receptor-positive, and HER2-negative locally advanced or metastatic breast cancer is also provided, wherein the combination is administered as a combination therapy comprising: a. QD administration of GDC-0077 on days 1 to 28 of the first 28-day cycle; b. QD administration of palbociclib on days 1 to 21 of the first 28-day cycle; and c. QD administration of fulvestrant on days 1 and 15 of the first 28-day cycle.

[0021] Also provided is the use of a combination of drugs for treating PIK3CA-mutated, hormone receptor-positive and HER2-negative locally advanced or metastatic breast cancer, wherein the combination comprises GDC-0077, palbociclib and fulvestrant, and wherein the combination is administered over a 28-day cycle.

[0022] Also provided is the use of a combination of drugs for treating PIK3CA-mutated, hormone receptor-positive, and HER2-negative locally advanced or metastatic breast cancer, wherein the combination is administered as a combination therapy comprising: a. QD administration of GDC-0077 on days 1 to 28 of the first 28-day cycle; b. QD administration of palbociclib on days 1 to 21 of the first 28-day cycle; and c. QD administration of fulvestrant on days 1 and 15 of the first 28-day cycle.

[0023] In some of these embodiments, the dosing regimen further comprises one or more additional 28-day cycles, comprising: a. administering GDC-0077 on days 1 to 28 of each additional 28-day cycle; b. administering palbociclib on days 1 to 21 of each additional 28-day cycle; and c. administering fulvestrant on day 1 of each additional 28-day cycle (or approximately every 4 weeks).

[0024] In some of these embodiments, GDC-0077 is administered in a dose of 9 mg, for example, as an oral tablet. In some embodiments, palbociclib is administered in a dose of 125 mg, for example, as an oral capsule or tablet. In some embodiments, fulvestrant is administered in a dose of 500 mg, for example, by intramuscular (IM) injection or infusion.

[0025] In some embodiments, a method of treating a patient with hormone receptor-positive and HER2-negative locally advanced or metastatic breast cancer is provided, the method comprising administering a combination therapy to the patient comprising GDC-0077, palbociclib, and letrozole, wherein the combination therapy is administered over a 28-day cycle.

[0026] In some embodiments, a method of treating a patient with PIK3CA-mutated, hormone receptor-positive, and HER2-negative locally advanced or metastatic breast cancer is provided, the method comprising administering a combination therapy to the patient, the combination therapy comprising a dosing regimen comprising: a. administering GDC-0077 via QD on days 1 to 28 of the first 28-day cycle; b. administering palbociclib via QD on days 1 to 21 of the first 28-day cycle; and c. administering letrozole via QD on days 1 to 28 of the first 28-day cycle.

[0027] In some of these embodiments, the method further includes one or more additional 28-day cycles, comprising: a. administering GDC-0077 on days 1 to 28 of each additional 28-day cycle; b. administering palbociclib on days 1 to 21 of each additional 28-day cycle; and c. administering letrozole on days 1 to 28 of each additional 28-day cycle.

[0028] A combination for treating PIK3CA-mutated, hormone receptor-positive and HER2-negative locally advanced or metastatic breast cancer is also provided, wherein the combination comprises GDC-0077, palbociclib and letrozole, and wherein the combination is administered over a 28-day cycle.

[0029] A combination therapy for treating PIK3CA-mutated, hormone receptor-positive, and HER2-negative locally advanced or metastatic breast cancer is also provided, wherein the combination is administered as a combination therapy comprising: a. administration of GDC-0077 by QD on days 1 to 28 of the first 28-day cycle; b. administration of palbociclib by QD on days 1 to 21 of the first 28-day cycle; and c. administration of letrozole by QD on days 1 to 28 of the first 28-day cycle.

[0030] Also provided is the use of a combination of drugs for treating PIK3CA-mutated, hormone receptor-positive and HER2-negative locally advanced or metastatic breast cancer, wherein the combination comprises GDC-0077, palbociclib and letrozole, and wherein the combination is administered over a 28-day cycle.

[0031] Also provided is the use of a combination of drugs for treating PIK3CA-mutated, hormone receptor-positive, and HER2-negative locally advanced or metastatic breast cancer, wherein the combination is administered as a combination therapy comprising: a. administering GDC-0077 by QD on days 1 to 28 of the first 28-day cycle; b. administering palbociclib by QD on days 1 to 21 of the first 28-day cycle; and c. administering letrozole by QD on days 1 to 28 of the first 28-day cycle.

[0032] In some of these embodiments, the dosing regimen further comprises one or more additional 28-day cycles, comprising: a. administering GDC-0077 on days 1 to 28 of each additional 28-day cycle; b. administering palbociclib on days 1 to 21 of each additional 28-day cycle; and c. administering letrozole on days 1 to 28 of each additional 28-day cycle.

[0033] In some of these embodiments, GDC-0077 is administered in amounts of 3 mg, 6 mg, or 9 mg, for example, as one or more oral tablets. In some embodiments, GDC-0077 is administered in amounts of 9 mg, for example, as an oral tablet. In some embodiments, palbociclib is administered in amounts of 125 mg, for example, as an oral capsule or tablet. In some embodiments, letrozole is administered in amounts of 2.5 mg, for example, as an oral tablet.

[0034] In a further embodiment, a method is provided for inhibiting tumor growth or producing / increasing tumor regression in a patient with PIK3CA-mutated, hormone receptor-positive, and HER2-negative locally advanced or metastatic breast cancer, the method comprising administering a combination therapy to the patient according to the methods detailed herein.

[0035] In another embodiment, a combination is provided for inhibiting tumor growth or producing / increasing tumor regression in patients with PIK3CA-mutated, hormone receptor-positive and HER2-negative locally advanced or metastatic breast cancer, according to the use of the combination detailed herein.

[0036] In another embodiment, there is provided a combination for manufacturing a drug that inhibits tumor growth or produces / increases tumor regression in patients with PIK3CA-mutated, hormone receptor-positive, and HER2-negative locally advanced or metastatic breast cancer, according to the combination or use detailed herein.

[0037] In some of these embodiments, the patient has locally advanced or metastatic breast cancer that is not treatable with curative therapies. In some embodiments, the patient has experienced disease progression during adjuvant endocrine therapy or within 12 months after completion of adjuvant endocrine therapy (e.g., using aromatase inhibitors or tamoxifen). In some embodiments, the patient has adequate hematologic and organ function within 14 days prior to the start of treatment. In some embodiments, the patient is a postmenopausal patient (e.g., a postmenopausal woman). In some embodiments, the patient is a premenopausal or perimenopausal patient (e.g., a premenopausal or perimenopausal woman). In some embodiments, the patient is male.

[0038] A further method for preventing or delaying the development of resistance in a tumor (e.g., breast cancer) to a therapy containing palbociclib is provided, comprising administering a combination therapy comprising GDC-0077, palbociclib, and fulvestrant, or a combination therapy comprising GDC-0077, palbociclib, and letrozole. In some embodiments, the combination therapy is administered according to any method as detailed herein.

[0039] Also provided is a combination for preventing or delaying the development of resistance in tumors (e.g., breast cancer) to a therapy containing palbociclib, wherein the combination comprises GDC-0077, palbociclib, and fulvestrant, or comprises GDC-0077, palbociclib, and letrozole. In some embodiments, the combination is administered according to any use as detailed herein.

[0040] Also provided is the use of a combination of medicines for preventing or delaying the development of resistance in tumors (e.g., breast cancer) to a therapy containing palbociclib, said combination comprising GDC-0077, palbociclib, and fulvestrant, or comprising GDC-0077, palbociclib, and letrozole. In some embodiments, the combination is administered according to any of the uses detailed herein. [Brief Description of the Drawings]

[0041] Figure 1 shows the effects of each single agent (P, F, and G), dual combination (P+F, G+F, and G+P), and triple combination (G+P+F) in a mouse model of MCF-7 PIK3CA mutant E545K ER+ breast cancer xenograft, in which each mouse (N = 12) received 25 mg / kg (oral, QD) GDC-0077 (G) for 21 days, 50 mg / kg (oral, QD) palbociclib (P) for 21 days, and 200 mg / kg (sc, weekly) fulvestrant (F) for 3 weeks. Figure 2 shows body weight changes in a mouse model of MCF-7 PIK3CA mutant E545K ER+ breast cancer xenograft, where each mouse received 50 mg / kg (oral, QD) GDC-0077 (G) for 21 days, 50 mg / kg (oral, QD) palbociclib (P) for 21 days, and 200 mg / kg (sc, weekly) fulvestrant (F) for 3 weeks. Figure 3 shows the single-agent antitumor activity of GDC-0077 in a phase 1a clinical study. Figure 4 shows the antitumor activity of GDC-0077 (G) in combination with letrozole (L). Footnote: *p110α mutation: KIN = kinase domain (H1047, M1043); HEL = helical domain (E545, E542, Q546); Mul = multiple mutations; O = other: N345K. **Previous AI = Previous aromatase inhibitor; A = Adjuvant; M = Metastatic status; B = Both adjuvant and metastatic. Shaded squares in the treatment time row indicate treatment > 6 months. Figure 5 shows the antitumor activity of GDC-0077 (G) in combination with palbociclib (P) and letrozole (L). Footnote: *p110α mutation: kinase domain (H1047, M1043); HEL = helical domain (E545, E542, Q546); Mul = multiple mutations. **Previous AI = Previous aromatase inhibitor; A = Adjuvant; M = Metastatic status; B = Both adjuvant and metastatic. ***Non-CR because the patient still has unmeasurable disease. Shaded squares in the treatment time row indicate treatment > 6 months. Figure 6 shows the antitumor activity of GDC-0077 (G) in combination with fulvestrant (F). Figure 7 shows the antitumor activity of sefliximab in combination with palbociclib and fulvestrant in group E. Footnote: *p110α mutations: HEL, helical (E545, E542, Q546); KIN, kinase (H1047, M1043); MUL, multiple mutations.Mutations were defined using local and / or central cobas® tests. †Previous AI, previous aromatase inhibitor; A, adjuvant; M, metastatic status; B = both adjuvant and metastatic. AI, aromatase inhibitor; CR, complete response; PD, disease progression; PR, partial response; SD, stable disease; SLD, sum of longest diameters. Shaded squares in the treatment time row indicate treatment > 6 months. Figure 8 shows the antitumor activity of estradiol in combination with palbociclib and fulvestrant in group F. Footnote: *p110α mutations: HEL, helical (E545, E542, Q546); KIN, kinase (H1047, M1043); MUL, multiple mutations. Mutations were defined using local and / or central cobas® tests. †Previous AI, previous aromatase inhibitor; A, adjuvant; M, metastatic status; B = both adjuvant and metastatic. AI, aromatase inhibitor; CR, complete remission; PD, disease progression; PR, partial remission; SD, stable disease; SLD, sum of longest diameters. Shaded squares in the treatment time row indicate treatment > 6 months.

Implementation Method

[0042] Cross-reference to related applications

[0043] This application claims the benefits of U.S. Provisional Patent Application No. 62 / 943,185, filed December 3, 2019; U.S. Provisional Patent Application No. 62 / 946,400, filed December 10, 2019; and U.S. Provisional Patent Application No. 63 / 014,965, filed April 24, 2020, the contents of which are incorporated herein by reference in their entirety.

[0044] Definition

[0045] When used in this specification and the claims, the words “comprise” and “include” are intended to specify the presence of the said feature, integer, component, or step, but they do not exclude the presence or inclusion of one or more other features, integers, components, steps, or groups thereof.

[0046] The terms "treat" and "treatment" refer to therapeutic procedures and preventive or deterrent measures aimed at preventing or mitigating (alleviating) undesirable physiological changes or conditions, such as the growth, development, or spread of cancer. For the purposes of this invention, beneficial or desired clinical outcomes include, but are not limited to, symptom relief, disease severity reduction, disease stability (i.e., no worsening), delay or slowing of disease progression, improvement or alleviation of disease condition, and remission (whether partial or complete), whether detectable or undetectable. "Treatment" may also mean extended survival compared to expected survival without treatment. Those in need of treatment include those already suffering from a condition or disability, those susceptible to developing a condition or disability, or those with a condition or disability to be prevented.

[0047] The phrase “therapeutic effective amount” refers to the amount of the compound of the present invention that (i) treats a particular disease, symptom, or disorder, (ii) alleviates, improves, or eliminates one or more symptoms of a particular disease, symptom, or disorder, or (iii) prevents or delays the onset of one or more symptoms of the particular disease, symptom, or disorder as described herein. In the case of cancer, a therapeutically effective amount of the drug may reduce the number of cancer cells; reduce tumor size; inhibit (i.e., to some extent slow down or preferably stop) the infiltration of cancer cells into surrounding organs; inhibit (i.e., to some extent slow down or preferably stop) tumor metastasis; inhibit tumor growth to some extent; and / or alleviate one or more of the symptoms associated with the cancer to some extent. To some extent, the drug may prevent the growth of and / or kill existing cancer cells; it may be growth-inhibiting and / or cytotoxic. For cancer therapy, efficacy may be measured, for example, by assessing time to disease progression (TTP) and / or determining the response rate (RR).

[0048] "Time to deterioration" or "TTP" refers to the time from randomization to objective tumor deterioration.

[0049] "Objective Response Rate" or "ORR" refers to the proportion of patients who have achieved two consecutive complete or partial responses with a confirmed interval of ≥ 4 weeks, as determined by investigators according to RECIST v1.1.

[0050] “Best Overall Response Rate” or “BOR” refers to the proportion of patients with CR or PR as determined by the investigator according to RECIST v1.1.

[0051] "Duration of Remission" or "DOR" refers to the time from the first occurrence of a documented objective remission to the time from disease exacerbation or death from any cause as determined by the researcher according to RECIST v1.1, whichever occurs first.

[0052] "Clinical benefit rate" or "CBR" refers to the proportion of patients with stable disease for at least 24 weeks or with a proven complete or partial response, as determined by investigators according to RECIST v1.1.

[0053] "Total Lifetime" or "OS" refers to the time from registration to death from any cause.

[0054] “Time to worsening pain (TTD)” refers to the time from randomization to the first recorded increase of ≥ 2 points in the “most severe pain” item from baseline in the Short Version of the Brief Pain Scale-SF (BPI-SF).

[0055] “Time to deterioration in physical function (TTD)” refers to the time from randomization to the first recording of a decrease of ≥ 10 points from baseline in the European Organization for Research and Treatment of Cancer Quality of Life Core Questionnaire 30 (EORTC QLQ-C30) Physical Function Scale (items 1-5).

[0056] “Time to Deterioration of Role Function (TTD)” refers to the time from randomization to the first recorded decrease of ≥ 10 points from baseline in the EORTC QLQ-C30 Role Function Scale (items 6 and 7).

[0057] “Time to deterioration of overall health status (GHS) / health-related quality of life (HRQoL) (TTD)” refers to the time from randomization to the first recording to a decrease of ≥ 10 points from baseline in the EORTC QLQ-30 GHS / HRQoL scale (items 29 and 30).

[0058] "Disease-free survival" or "PFS" refers to the time from registration to the date on which disease progression occurs or death from any cause, as determined by the investigator in RECIST v1.1, whichever comes first.

[0059] "Complete remission" or "CR" refers to the disappearance of all target and non-target lesions and (if applicable) the normalization of tumor marker levels.

[0060] "Partial remission", "PR" or "non-CR / non-PrD" refers to the persistence of one or more non-target lesions and / or (if applicable) - tumor marker levels remain above normal limits. PR may also refer to a reduction of ≥ 30% in the sum of the diameters of target lesions, without CR, new lesions or clear deterioration of non-target lesions.

[0061] "Deteriorating disease" or "PrD" refers to an increase of ≥ 20% in the total diameter of target lesions, a clear deterioration of non-target lesions, and / or the appearance of new lesions.

[0062] "Stable condition" or "SD" means that there is neither significant shrinkage that meets the criteria of CR or PR, nor sufficient increase in tumor growth that meets the criteria of PrD.

[0063] "Dosing period" or "cycle" refers to a period of time including dosing with one or more agents disclosed herein and, if necessary, a period of time excluding dosing with one or more agents disclosed herein. For example, the total duration of a cycle may be 28 days, including a 21-day dosing period with one or more agents and a 7-day suspension period. "Suspension period" refers to a period of time during which at least one of the agents disclosed herein is not dosed. In one embodiment, a suspension period refers to a period of time during which none of the agents disclosed herein are dosed.

[0064] "Dosing regimen" refers to a time period comprising one or more cycles in which the agent disclosed herein is administered, wherein each cycle may include administration of the agent disclosed herein at different time points in different amounts.

[0065] "QD" refers to the administration of the compound once a day.

[0066] Graded adverse events refer to a severity grading table established by NCI CTCAE. In one embodiment, adverse events are graded according to the following table. level Severity 1 Mild; asymptomatic or with mild symptoms; clinical or diagnostic observation only; or no intervention indicated. 2 Moderate; instructing minimal, localized, or non-invasive intervention; or involving age-appropriate instrumental activities of daily living. 3 Severe or medically significant but not immediately life-threatening; requires hospitalization or prolonged hospitalization; causes disability; or limits self-care activities in daily life. 4 The indication is that there are life-threatening consequences or that intervention is urgently needed. 5 Deaths related to adverse events

[0067] The term “detection” includes any means of detection, including direct and indirect detection.

[0068] The term “prognosis” as used herein refers to the prediction of the likelihood of death or worsening of a neoplastic disease such as cancer, including, for example, recurrence, metastatic spread, and drug resistance.

[0069] The term “prediction” (and grammatical variations thereof) is used herein to refer to the likelihood that a patient will have a favorable or unfavorable response to a drug or a group of drugs. In one embodiment, the prediction relates to the degree of response. In another embodiment, the prediction relates to whether a patient will survive and / or the likelihood of survival after treatment, such as treatment with a specific therapeutic agent and / or surgical resection of a primary tumor and / or chemotherapy for a period of time without cancer recurrence. By selecting the most appropriate treatment for any particular patient, the prediction method of the present invention can be used clinically to make treatment decisions. The prediction method of the present invention is a valuable tool in predicting whether a patient is likely to have a favorable response to a treatment regimen (such as a given treatment regimen), for example, including the administration of a given therapeutic agent or combination, surgical intervention, chemotherapy, etc., or whether it is likely that the patient will survive long-term after the treatment regimen.

[0070] When used according to the present invention, the term “increased resistance” to a particular therapeutic agent or treatment option refers to a decrease in remission to a standard dose of the drug or to a standard treatment regimen.

[0071] Any endpoint that indicates benefit to the patient may be used to evaluate “remission”, including but not limited to: (1) inhibition of tumor growth to some extent, including slowing or stopping growth completely; (2) reduction of the number of tumor cells; (3) reduction of tumor size; (4) inhibition (e.g., reduction, slowing or stopping) of tumor cell infiltration into adjacent surrounding organs and / or tissues; (5) inhibition (e.g., reduction, slowing or stopping) of metastasis; (6) enhancement of antitumor immune response, which may but not necessarily lead to tumor regression or rejection; (7) relief of one or more symptoms associated with the tumor to some extent; (8) increase of survival time after treatment; and / or (9) reduction of mortality at a given time point after treatment.

[0072] A "biomarker" is a characteristic that is objectively measured and assessed as an indicator of normal biological processes, pathological processes, or pharmacological responses to therapeutic interventions. Biomarkers can be of several types: predictive, prognostic, or pharmacodynamic (PD). Predictive biomarkers predict which patients may respond to or benefit from a particular therapy. Prognostic biomarkers predict the likely course of a patient's disease and can guide treatment. Pharmacodynamic biomarkers confirm drug activity and can optimize dosage and administration schedules.

[0073] By analyzing biological samples using one or more methods commonly used to establish pharmacodynamics (PD), “changes” or “regulations” in the state of biomarkers can be detected, including PIK3CA mutations or a group of PIK3CA mutations occurring in vitro or in vivo, including: (1) sequencing the genomic DNA or reverse transcription PCR product of the biological sample to detect one or more mutations; (2) assessing gene expression by quantifying information content or evaluating copy number; (3) detecting protein degradation, stabilization, or post-translational modifications such as phosphorylation or ubiquitination by analyzing proteins using immunohistochemistry (IHC), immunocytochemistry, ELISA, or mass spectrometry.

[0074] "Chemotherapy agent" is a biological (macromolecule) or chemical (small molecule) compound that can be used to treat cancer, regardless of its mechanism of action.

[0075] The term "instructions for use of a drug" is used to refer to instructions that are usually included in the commercial packaging of a therapeutic product, which contain information about the indications, usage, dosage, administration, contraindications and / or warnings for using such therapeutic products.

[0076] As used herein, the phrase “pharmaceutically acceptable salt” refers to pharmaceutically acceptable organic or inorganic salts of the compounds of the present invention. Exemplary salts include, but are not limited to, sulfates, citrates, acetates, oxalates, chlorides, bromides, iodides, nitrates, bisulfates, phosphates, acid phosphates, isonicotinates, lactates, salicylates, citrates, tartrates, oleates, tannates, pantothenates, bitartrates, ascorbic acid salts, succinates, maleates, gentianates, fumarates, gluconates, glucurons, sucrose salts, formates, benzoates, glutamates, methanesulfonates (or mesylates), ethanesulfonates, benzenesulfonates, p-toluenesulfonates, and pyrates (i.e., 1,1'-methylenebis-(2-hydroxy-3-naphthylcarbamate)). Pharmaceutically acceptable salts may involve the inclusion of another molecule, such as an acetate ion, a succinate ion, or other relative ions. The relative ion can be the organic or inorganic part of any stable parent compound with charge. Furthermore, pharmaceutically acceptable salts may have more than one charged atom in their structure. Instances of pharmaceutically acceptable salts having multiple charged atoms as part of their structure may have multiple relative ions. Therefore, pharmaceutically acceptable salts may have one or more charged atoms and / or one or more relative ions.

[0077] The desired pharmaceutically acceptable salt can be prepared by any suitable method available in the art. For example, the free base can be treated with inorganic acids, such as hydrochloric acid, hydrobromic acid, sulfuric acid, nitric acid, methanesulfonic acid, phosphoric acid and the like; or with organic acids, such as acetic acid, maleic acid, succinic acid, mandelic acid, fumaric acid, malonic acid, pyruvic acid, oxalic acid, glycolic acid, salicylic acid, piperanoside, such as glucuronic acid or galacturonic acid, α-hydroxy acids, such as citric acid or tartaric acid, amino acids, such as aspartic acid or glutamic acid, aromatic hydroxy acids, such as benzoic acid or cinnamic acid, sulfonic acids, such as p-toluenesulfonic acid or ethanesulfonic acid, or the like. Acids generally considered suitable for forming pharmaceutically useful or acceptable salts from basic pharmaceutical compounds are, for example, those discussed below: P. Stahl et al., Camille G. (ed.) Handbook of Pharmaceutical Salts. Properties, Selection and Use. (2002) Zurich: Wiley-VCH; S. Berge et al., Journal of Pharmaceutical Sciences (1977) 66(1) 1 19; P. Gould, International J. of Pharmaceutics (1986) 33 201 217; Anderson et al., The Practice of Medicinal Chemistry (1996), Academic Press, New York; Remington's Pharmaceutical Sciences, 18thed., (1995) Mack Publishing Co., Easton PA; and The Orange Book (Food & Drug Administration, Washington, DC, on its website). These disclosures are incorporated herein by reference.

[0078] The phrase “pharmaceutically acceptable” means that the substance or composition must be chemically and / or toxicologically compatible with the other components of the formulation and / or the patients treated with it.

[0079] As used herein, the term "synergistic" refers to a therapeutic combination that is more effective than the additive effect of two or more single agents. The determination of the synergistic interaction between the compounds of GDC-0077 or their pharmaceutically acceptable salts and one or more chemotherapeutic agents can be based on results obtained from the assays described herein. The analysis of these assay results can be performed using the Chou and Talalay combination method and dose-response analysis with CalcuSyn® software to obtain a combination index (Chou and Talalay, 1984, Adv. Enzyme Regul. 22:27-55). The combinations provided by this invention have been evaluated in several assay systems, and the data can be analyzed using the standard procedure for quantifying synergistic, additive, and antagonistic effects between anticancer agents as described in Chapter 2 of "New Avenues in Developmental Cancer Chemotherapy," Academic Press, 1987, by Chou and Talalay. A combination index value less than 0.8 indicates synergistic effects, a value greater than 1.2 indicates antagonistic effects, and a value between 0.8 and 1.2 indicates additive effects. Combination therapy can provide "synergistic effects" and is demonstrated to be "synergistic," meaning that the effect achieved when the active ingredients are used together is greater than the sum of the effects produced by using the compounds alone. Synergistic effects can be achieved when the active ingredients are: (1) co-formulated and administered or delivered simultaneously in a combined unit dose formulation; (2) delivered alternately or in parallel in separate formulations; or (3) by some other means. Synergistic effects can be achieved when delivered in alternating therapy, when the compounds are administered or delivered sequentially, for example, in different syringes or in separate pills or tablets. Generally, in alternating therapy, the effective doses of the active ingredients are administered sequentially, i.e., continuously, while in combination therapy, the effective doses of two or more active ingredients are administered together. The combined effect was assessed using the BLISS independence model and the highest single-agent (HSA) model (Lehár et al., 2007, Molecular Systems Biology 3:80). The BLISS score quantifies the synergistic effect of the single agent, with a BLISS score > 0 indicating a greater effect than simple addition. An HSA score > 0 indicates that the combined effect is greater than the maximum relief achieved by a single agent at the corresponding concentration.

[0080] Clinical Compounds

[0081] Ivlissey (also known as GDC-0077):

[0082] Iffulix (GDC-0077) is a potent, orally bioavailable, clinical-stage class I PI3Kα isoform (PI3Kα) selective inhibitor with >300-fold biochemical inhibition against other class I PI3Kβ, δ, and γ isoforms. Furthermore, compared to wild-type (WT) PI3K cells, it exhibits increased efficacy against tumor cells carrying mutant PI3K (Braun, M. et al., “Discovery of GDC-0077: A highly selective inhibitor of PI3K-alpha that induces degradation of mutant-p110 alpha protein” Abstracts of Papers, 254th ACS National Meeting & Exposition, Washington, DC, USA, August 20-24, 2017, MEDI-22; Garland, K. et al., “Discovery of novel class of alpha selective PI3K inhibitors” Abstracts of Papers, 254th ACS National Meeting & Exposition, Washington, DC, USA, August 20-24, 2017, MEDI-103; Hong, R. et al., "GDC-0077 is a selective PI3K alpha inhibitor that demonstrates robust efficacy in PIK3CA mutant breast cancer models as a single agent and in combination with standard of care therapies" 2017 San Antonio Breast Cancer Symposium, Dec. 5-9 2017, San Antonio, TX, Abstract Publication Number: PD4-14; Edgar, K.et al., “Preclinical characterization of GDC-0077, a specific PI3K alpha inhibitor in early clinical development” Cancer Research77(13 Supplement): Abstract 156 · July 2017). .

[0083] Ivlixi, CAS Registry No. 2060571-02-8, Genentech, Inc., USA 9650393; named (S)-2-((2-((S)-4-(difluoromethyl)-2-sideoxyoxazolin-3-yl)-5,6-dihydrobenzo[f]imidazo[1,2-d][1,4]oxazolin-9-yl)amino)propionic acid, having the following structure:

[0084] Ivlixi is also known as GDC-0077, RG6114, RO7113755, or chemically as (2S)-2-[[2-[(4S)-4-(difluoromethyl)-2-sideoxy-3-oxazinyl]-5,6-dihydroimidazo[1,2-d][1,4]benzoxazinyl-9-yl]amino]propionylamine.

[0085] GDC-0077 exerts its activity by binding to the ATP-binding site of PI3K, thereby inhibiting the phosphorylation of membrane-bound 4,5-phosphatidylinositol diphosphate (PIP2) to 3,4,5-phosphatidylinositol triphosphate (PIP3). Inhibition of PIP2 to PIP3 phosphorylation reduces downstream activation of AKT and pS6, leading to reduced cell proliferation, metabolism, and angiogenesis. Non-clinical studies have demonstrated that GDC-0077 specifically degrades the mutant p110α, inhibits the proliferation of PIK3CA mutant breast cancer cell lines and induces their apoptosis, inhibits tumor growth in PIK3CA mutant human breast cancer xenograft models, and reduces downstream PI3K pathway markers, including pAKT (phosphorylated AKT), pPRAS40, and pS6.

[0086] Pabocicini:

[0087] Palbociclib is a selective inhibitor of cyclin-dependent kinases CDK4 and CDK6 (Finn et al., (2009) Breast Cancer Research: BCR11 (5):R77; Rocca et al., (2014) Expert Opin Pharmacother15 (3):407–20; US 6936612; US 7863278; US 7208489; US 7456168). Palbociclib can be prepared and characterized as described in US 7345171. IBRANCE® is approved for the treatment of breast cancer.

[0088] Palbociclib (PD-0332991, IBRANCE®, Pfizer, Inc., CAS Reg. No. 571190-30-2), named 6-acetylated-8-cyclopentyl-5-methyl-2-(5-(piperidin-1-yl)pyridin-2-ylamino)pyrido[2,3-d]pyrimidin-7(8H)-one, has the following structure:

[0089] Pabociclib is a CDK4 / 6 inhibitor and is effective in treating postmenopausal HR+ (positive) / HER2- (negative) breast cancer patients when used in combination with letrozole or fulvestrant. The main toxicity of palbociclib when used in combination with letrozole or fulvestrant is neutropenia (Finn et al., (2015) Lancet Oncol 16:25-35; Turner et al., (2015) N Engl J Med 373:209-19). When used in combination with letrozole, 36% of patients require a ≥1 dose reduction of palbociclib; dose maintenance and cycle delays were reported in 70% and 68% of patients, respectively (Finn et al., (2016) J Clin Oncol 34 (suppl; abstr 507)). When used in combination with fulvestrant, 34% of patients required a dose reduction of ≥1 bar of palbociclib; dose maintenance and cycle delays were reported in 54% and 36% of patients, respectively (Cristofanilli et al., (2016) Lancet Oncol 17:425-39). Myelosuppression is a potential toxicity of GDC-0077.

[0090] Other exemplary CDK4 / 6 inhibitors include, but are not limited to: ribocinib (succinic acid-7-cyclopentyl-N,N-dimethyl-2-{[5-(piperidin-1-yl)pyridin-2-yl]amino}-7H-pyrrolo[2,3-d]pyrimidin-6-methamide (1 / 1; sold as KISQALI®); abecine (2-pyrimidinylamine, N-[5-[(4-ethyl-1-piperidin-1-methyl]-2-pyridinyl]-5-fluoro-4-[4-fluoro-2-methyl-1-(1-methylethyl)-1H-benzimidazol-6-yl], sold as VERZENIO® (for sale); and taracinone (2'-((5-(4-methylpiperidin-1-yl)pyridin-2-yl)amino)-7',8'-dihydro-6'H-spiro(cyclohexane-1,9'-piperido(1',2':1,5)pyrrolo(2,3-d)pyrimidine)-6'-one).

[0091] Fluvestran:

[0092] Fulvestrant is an ER antagonist and is effective in treating postmenopausal HR+ breast cancer patients with relatively good tolerability. The expected toxicities of GDC-0077 and fulvestrant do not overlap. It is important to test the combination of GDC-0077 with letrozole and fulvestrant because these endocrine therapies have different mechanisms of action, different pharmacokinetic properties, and different potential drug-drug interactions (DDIs) with GDC-0077.

[0093] Flavorstant (FASLODEX®, AstraZeneca, CAS Reg. No. 129453-61-8) has been approved by the FDA for the treatment of hormone receptor-positive (HR+) metastatic breast cancer in postmenopausal women whose disease has progressed after anti-estrogen therapy (Kansra (2005) Mol Cell Endocrinol 239(1-2):27–36; Flemming et al., (2009) Breast Cancer Res Treat. May; 115(2):255-68; Valachis et al., (2010) Crit Rev Oncol Hematol. Mar; 73(3):220-7). Fulvestant is an estrogen receptor (ER) antagonist without agonist activity, which works by downregulating and degrading estrogen receptors (Croxtall (2011) Drugs 71(3):363–380). Fulvestrant is also a selective estrogen receptor downregulator (SERD).

[0094] Fluorvestrant is named (7α,17β)-7-{9-[(4,4,5,5,5-pentafluoropentyl)sulfinyl]nonyl}estradiol-1,3,5(10)-trien-3,17-diol and has the following structure:

[0095] Fulvestrant is a reversible steroid ER antagonist that directly competes with estrogen for ER binding and does not possess the partial agonist properties of tamoxifen. Upon binding to the ER, it blocks estrogen signaling and increases ER protein degradation. Fulvestrant has approximately 100 times greater affinity for the ER than tamoxifen (Howell et al., (2000) Cancer 89:817-25). Fulvestrant (250 mg once monthly) was approved by the FDA in 2002 and by the EMA in 2004 for the treatment of HR-positive mycobacterial chorionic purpura (MBC) in postmenopausal women whose disease has worsened following anti-estrogenic therapy. In multicenter phase III studies, fulvestrant was found to be at least equivalent to anastrozole (a nonsteroidal AI) in second-line treatment (Howell et al., (2002) J Clin Oncol 20:3396-3403; Osborne CK et al., (2002) J Clin Oncol 20:3386-95). Fulvestrant was also as effective as tamoxifen in first-line treatment of advanced breast cancer (Howell et al., (2004) J Clin Oncol 22:1605-1613), and showed some activity in patients with metastatic disease after AI, similar to the nonsteroidal AI exemestane (Chia et al., (2008) J Clin Oncol 26:1664-1670). High-dose fulvestrant (500 mg once monthly) has been shown to be at least as effective as anastrozole in terms of clinical benefit rate (CBR) and overall response rate, and is significantly associated with better time to progression of disease as first-line treatment in women with advanced HR-positive breast cancer (Robertson et al., (2009) J Clin Oncol 27:4530-4535). High-dose fulvestrant has recently been shown to have superior disease-free survival (PFS) with 500 mg compared to patients treated with 250 mg in women with ER-positive advanced breast cancer (Di Leo et al., (2010) J Clin Oncol 28:4594-4600). In these studies, fulvestrant (250 mg and 500 mg) was well tolerated and produced less estrogenic effects compared to tamoxifen, and less arthralgia compared to the AI ​​anastrozole (Osborne et al., (2002) J Clin Oncol 20:3386-3395). These results led to the approval of once-monthly 500 mg fulvestrant as the currently approved recommended dose in the US and EU (2010) for postmenopausal women whose disease has spread after AI treatment.These studies demonstrate that fulvestrant is an important treatment option for patients with advanced breast cancer and is therefore considered an appropriate control therapy in this study.

[0096] Letrozole:

[0097] Letrozole is effective in treating postmenopausal HR+ breast cancer patients with relatively good tolerance. The expected toxicities of GDC-0077 and letrozole do not overlap. Letrozole (FEMARA®, Novartis Pharm.) is an oral non-steroidal aromatase inhibitor used to treat postoperative hormone-responsive breast cancer (Bhatnagar et al., (1990) J. Steroid Biochem. and Mol. Biol. 37:1021; Lipton et al., (1995) Cancer 75:2132; Goss, PE and Smith, RE (2002) Expert Rev. Anticancer Ther. 2:249-260; Lang et al., (1993) The Journal of Steroid Biochem. and Mol. Biol. 44 (4–6):421–8; EP 236940; US 4978672). FEMARA® has been approved by the FDA for the treatment of postmenopausal women with hormone receptor-positive (HR+) or unknown receptor status locally or metastatic breast cancer.

[0098] Letrozole is named 4,4'-((1H-1,2,4-triazol-1-yl)methylene)dibenzylnitrile (CAS Reg. No. 112809-51-5), and its structure is as follows:

[0099] Combination Therapy

[0100] The present invention provides a combination therapy comprising a PI3K inhibitor (e.g., GDC-0077), a CDK4 / 6 inhibitor (e.g., palbociclib, ribociclib, or abeciclib), and an endocrine therapy (e.g., fulvestrant or letrozole). In one embodiment, a combination or combination therapy comprising a PI3Kα (PI3Kα) inhibitor (e.g., GDC-0077), a CDK4 / 6 inhibitor (e.g., palbociclib, ribociclib, or abeciclib), and an endocrine therapy (e.g., fulvestrant or letrozole). In one embodiment, the combination or combination therapy comprises GDC-0077, palbociclib, and fulvestrant. In another embodiment, the combination or combination therapy comprises GDC-0077, palbociclib, and letrozole.

[0101] The combination or combination therapy described herein may be provided as a kit containing one or more agents for administration. In one embodiment, the kit contains GDC-0077 and fulvestrant. In one embodiment, the kit contains GDC-0077, palbociclib, and letrozole. In another embodiment, the kit contains GDC-0077, palbociclib, and fulvestrant. In one embodiment, the agents of the combination and combination therapy disclosed herein are supplied in the kit in a form prepared for administration or, for example, for reconstitution. The kits disclosed herein may contain instructions for use such as packaging inserts. In one embodiment, such instructions for use are packaging inserts – one for each agent in the kit.

[0102] Further provided is a kit for implementing the methods detailed herein, comprising pharmaceutical compositions or combination therapies as described herein and instructions for use in treating breast cancer.

[0103] Kits typically contain suitable packaging. Kits may contain one or more containers containing any pharmaceutical composition as described herein. Each component (if there is more than one component) may be packaged in a separate container, or some components may be combined in one container where cross-reactivity and shelf life are permissible. One or more components of the kit may be sterile and / or may be contained within sterile packaging.

[0104] Method

[0105] This article provides a method for treating hormone receptor-positive and HER2-negative locally advanced or metastatic breast cancer. In one embodiment, the method comprises treating a patient with hormone receptor-positive and HER2-negative locally advanced or metastatic breast cancer by administering a combination therapy comprising a PI3K inhibitor (preferably a PI3Kα inhibitor, such as GDC-0077), a CDK4 / 6 inhibitor (e.g., palbociclib, ribociclib, or abeciclib), and endocrine therapy (e.g., fulvestrant or letrozole).

[0106] A method of treating patients with hormone receptor-positive and HER2-negative (HR+ / HER2-) locally advanced or metastatic breast cancer is also provided, comprising administering a therapeutically effective amount of GDC-0077 or a pharmaceutically acceptable salt thereof, a CDK4 / 6 inhibitor (e.g., palbociclib, ribociclib, or abeciclib), and endocrine therapy (e.g., fulvestrant or letrozole). In some embodiments, the CDK4 / 6 inhibitor is palbociclib. In some embodiments, the CDK4 / 6 inhibitor is ribociclib or abeciclib. In some embodiments, the endocrine therapy is fulvestrant. In some embodiments, the endocrine therapy is letrozole.

[0107] In one embodiment, a method for treating hormone receptor-positive and HER2-negative (HR+ / HER2-) locally advanced or metastatic breast cancer in a patient is provided, comprising administering a therapeutically effective amount of GDC-0077 or a pharmaceutically acceptable salt thereof, palbociclib, and fulvestrant.

[0108] In another embodiment, this disclosure provides a method for treating hormone receptor-positive and HER2-negative (HR+ / HER2-) locally advanced or metastatic breast cancer in a patient, the method comprising administering a therapeutically effective amount of GDC-0077 or a pharmaceutically acceptable salt thereof, palbociclib, and letrozole.

[0109] In some embodiments, a method of treating a patient with hormone receptor-positive and HER2-negative locally advanced or metastatic breast cancer is provided, the method comprising administering a combination therapy to the patient comprising GDC-0077, palbociclib, and fulvestrant, wherein the combination therapy is administered over a 28-day cycle.

[0110] In some embodiments, a method of treating a patient with hormone receptor-positive and HER2-negative locally advanced or metastatic breast cancer is provided, the method comprising administering a combination therapy to the patient, the combination therapy comprising a dosing regimen comprising: a. administering GDC-0077 via QD on days 1 to 28 of the first 28-day cycle; b. administering palbociclib via QD on days 1 to 21 of the first 28-day cycle; and c. administering fulvestrant on days 1 and 15 of the first 28-day cycle.

[0111] In some of these embodiments, the method further includes one or more additional 28-day cycles, comprising: a. administering GDC-0077 on days 1 to 28 of each additional 28-day cycle; b. administering palbociclib on days 1 to 21 of each additional 28-day cycle; and c. administering fulvestrant on day 1 of each additional 28-day cycle (or approximately once every 4 weeks).

[0112] In some embodiments, the patient has PIK3CA mutation, hormone receptor positive, Her2 negative, locally advanced or metastatic breast cancer. In some embodiments, the patient has mutated PIK3CA with mutations at one or more of positions 88, 106, 111, 118, 345, 420, 453, 542, 545, 546, 1043, 1047, and 1049. In some embodiments, the patient has mutated PIK3CA with mutations at one or more of positions H1047, E545, E542, Q546, N345, C420, M1043, G1049, E453, K111, G106, G118, and R88. In some embodiments, the patient has a PIK3CA mutation containing one or more mutations selected from the group consisting of the following: H1047D / I / L / N / P / Q / R / T / Y, E545A / D / G / K / L / Q / R / V, E542A / D / G / K / Q / R / V, Q546E / H / K / L / P / R, N345D / H / I / K / S / T / Y, C420R, M1043I / T / V, G1049A / C / D / R / S, E453A / D / G / K / Q / V, K111N / R / E, G106A / D / R / S / V, G118D, and R88Q. In some embodiments, the patient has a PIK3CA mutation containing one or more mutations selected from the group consisting of: E542K, E545K, Q546R, H1047L, and H1047R. In some embodiments, the patient has breast cancer manifested by PIK3CA mutations selected from the following groups: H1047D / I / L / N / P / Q / R / T / Y, E545A / D / G / K / L / Q / R / V, E542A / D / G / K / Q / R / V, Q546E / H / K / L / P / R, N345D / H / I / K / S / T / Y, C420R, M1043I / T / V, G1049A / C / D / R / S, E453A / D / G / K / Q / V, K111N / R / E, G106A / D / R / S / V, G118D, and R88Q. In some embodiments, the patient has breast cancer exhibiting a PIK3CA mutation selected from the group consisting of: E542K, E545K, Q546R, H1047L, and H1047R. In some embodiments, the patient has a mutated PIK3CA containing mutations selected from the group consisting of: E542K, E545K, Q546R, H1047L, and H1047R, as well as a second mutation (e.g., a second mutation selected from E453Q / K, E726K, and M1043L / I).In some embodiments, the patient has breast cancer exhibiting a PIK3CA mutation, which is a double mutation selected from the group consisting of the following: E542K + E453Q / K, E542K + E726K, E542K + M1043L / I; E545K + E453Q / K, E545K + E726K, E545K + M1043L / I; H1047R + E453Q / K, and H1047R + E726K.

[0113] The tumor status of PIK3CA mutations can be assessed by centralized blood testing or local testing of blood or tumor tissue. In some embodiments, the central test for identifying eligible PIK3CA mutations is the FoundationOne Liquid Clinical Trial Assay performed by Foundation Medicine, Inc. In some embodiments, local testing of blood or tumor tissue is performed using sponsor-approved PCR or NGS-based analysis in CLIA-certified or equivalent laboratories.

[0114] In some embodiments, a method of treating a patient with hormone receptor-positive and HER2-negative locally advanced or metastatic breast cancer is provided, the method comprising administering a combination therapy to the patient comprising GDC-0077, palbociclib, and letrozole, wherein the combination therapy is administered over a 28-day cycle.

[0115] In some embodiments, a method of treating a patient with PIK3CA-mutated, hormone receptor-positive, and HER2-negative locally advanced or metastatic breast cancer is provided, the method comprising administering a combination therapy to the patient, the combination therapy comprising a dosing regimen comprising: a. administering GDC-0077 via QD on days 1 to 28 of the first 28-day cycle; b. administering palbociclib via QD on days 1 to 21 of the first 28-day cycle; and c. administering letrozole via QD on days 1 to 28 of the first 28-day cycle.

[0116] In some of these embodiments, the method further includes one or more additional 28-day cycles, comprising: a. administering GDC-0077 on days 1 to 28 of each additional 28-day cycle; b. administering palbociclib on days 1 to 21 of each additional 28-day cycle; and c. administering letrozole on days 1 to 28 of each additional 28-day cycle.

[0117] In one embodiment, the method includes a combination therapy comprising (i) GDC-0077; (ii) fulvestrant; and (iii) palbociclib. In one embodiment, the method includes a combination therapy administered according to the dosing regimen disclosed herein, comprising (i) GDC-0077; (ii) palbociclib; and (iii) fulvestrant.

[0118] In one embodiment, the method includes a combination therapy comprising (i) GDC-0077; (ii) fulvestrant; and (iii) palbociclib. In one embodiment, the method includes a combination therapy administered according to the dosing regimen disclosed herein, comprising (i) GDC-0077; (ii) palbociclib; and (iii) letrozole.

[0119] In a further embodiment, a method is provided for inhibiting tumor growth or producing / increasing tumor regression in a patient with PIK3CA-mutated, hormone receptor-positive, and HER2-negative locally advanced or metastatic breast cancer, the method comprising administering a combination therapy to the patient according to the methods detailed herein.

[0120] In some embodiments, estrogen receptor (ER) positive and / or progesterone receptor positive tumors are defined, according to the American Society of Clinical Oncology / College of American Pathologists (ASCO / CAP) guidelines, as based on the most recent tumor biopsy section and locally assessed as having ≥ 1% positive tumor cell staining.

[0121] In some embodiments, HER2-negative tumors are defined, according to the ASCO / CAP guidelines, as having a HER2 immunohistochemical (IHC) score of 0 or 1+, or an IHC score of 2+ accompanied by negative fluorescence, chromogenic or silver in situ hybridization tests indicating no HER2 gene amplification, or a HER2 / CEP17 ratio of < 2.0 based on the most recent tumor biopsy and locally assessed.

[0122] In some embodiments, the patient is a woman or man aged ≥ 18 years.

[0123] In some embodiments, the patient is a postmenopausal patient (e.g., a postmenopausal woman). A postmenopausal woman is defined by at least one of the following criteria: (1) age ≥ 60 years; (2) age < 60 years and 12 months without menstruation, plus follicle-stimulating hormone and plasma estradiol levels assessed by a local laboratory within the postmenopausal range without oral contraceptives, hormone replacement therapy, or gonadotropin-releasing hormone agonists or antagonists; (3) a documented bilateral oophorectomy (≥ 14 days prior to the first treatment on day 1 of cycle 1 and restored to baseline).

[0124] In some embodiments, the patient is a premenopausal or perimenopausal woman (i.e., does not meet the postmenopausal criteria) and has been on luteinizing hormone-releasing hormone (LHRH) agonist therapy (e.g., goserelin or leuprorelin) for at least 2 weeks prior to day 1 of cycle 1 and has continued to do so during the study treatment.

[0125] In some embodiments, the patient is male and has been treated with an LHRH agonist (e.g., goserelin or leuprorelin) for at least 2 weeks prior to day 1 of cycle 1 and has continued to do so during the study treatment.

[0126] The agents disclosed herein may be administered according to the packaging insert. In one embodiment of the method disclosed herein, the agents may be administered in the effective amount disclosed herein. In some embodiments, palbociclib, fulvestrant, or letrozole, if applicable, are administered at their approved doses via the approved route of administration.

[0127] The agents in the combination therapies detailed herein may be administered simultaneously or sequentially. Two of the three agents in a combination therapy may be administered simultaneously, while the third agent may be administered before or after. For example, in one embodiment of the method described herein, the administration of GDC-0077 occurs before the administration of another agent (e.g., fulvestrant or letrozole). In one embodiment of the method disclosed herein, the administration of GDC-0077 occurs before the administration of fulvestrant or letrozole, and the administration of fulvestrant occurs before the administration of a CDK4 / 6 inhibitor (e.g., palbociclib). In another embodiment, the administration of GDC-0077 occurs before or simultaneously with palbociclib, and is followed by the administration of fulvestrant or letrozole.

[0128] In some embodiments, GDC-0077 is administered in amounts of 3 mg, 6 mg, or 9 mg, for example, as one or more oral tablets. In some embodiments, GDC-0077 is administered orally at a daily dose of 9 mg. In some of these embodiments, GDC-0077 is administered in amounts of 9 mg, for example, as oral tablets.

[0129] In one embodiment of the method disclosed herein, palbociclib is administered as a dose of the three-component combination therapy disclosed herein. In one embodiment, palbociclib is administered orally at a dose of 125 mg, 100 mg, or 75 mg. In another embodiment, palbociclib is administered orally at a dose of 125 mg. In another embodiment, palbociclib is administered orally at a dose of 100 mg. In yet another embodiment, palbociclib is administered orally at a dose of 75 mg. In such embodiments, palbociclib is administered via QD on days 1 to 21 of each 28-day cycle. In another embodiment of the method disclosed herein, palbociclib is administered according to the package insert. In one embodiment, palbociclib is administered orally via QD on days 1 to 21 of each 28-day cycle at the dose disclosed herein. In yet another embodiment, the dose of palbociclib is varied from the initial dose (e.g., reduced). In one such embodiment, the amount of palbociclib is reduced from 125 mg to 100 mg, and in one embodiment, it may be further reduced to 75 mg. In another embodiment, palbociclib is administered using the dosing regimen disclosed herein.

[0130] In some embodiments, palbociclib is administered in a dose of 125 mg, for example, in oral capsules or tablets.

[0131] In another embodiment of the method disclosed herein, fulvestrant is administered at a dose of approximately 500 mg. In one embodiment of the method disclosed herein, fulvestrant is administered according to the package insert. In one embodiment, fulvestrant is administered as two separate intramuscular injections of 250 mg. In another embodiment, fulvestrant is administered according to the dosing regimen disclosed herein. In one such embodiment, fulvestrant is administered on days 1 and 15 of the first 28-day cycle, and on day 1 of each subsequent 28-day cycle thereafter.

[0132] In some embodiments, fulvestrant is administered in a dose of 500 mg, for example by intramuscular (IM) infusion.

[0133] In another embodiment of the method disclosed herein, letrozole is administered at a dose of about 2.5 mg. In one embodiment of the method disclosed herein, letrozole is administered according to a packaging insert. In another embodiment, fulvestrant is administered according to the dosing regimen disclosed herein. In one such embodiment, letrozole is administered orally at a dose of about 2.5 mg once daily.

[0134] In some embodiments, letrozole is administered in an amount of 2.5 mg, for example, as an oral tablet.

[0135] In one embodiment, the method disclosed herein comprises administering the combination therapy disclosed herein according to a dosing regimen comprising a 28-day cycle. In another embodiment, the method disclosed herein comprises administering the combination therapy disclosed herein according to a dosing regimen comprising a first 28-day cycle and subsequent additional 28-day cycles. In another embodiment, the method disclosed herein comprises administering the combination therapy disclosed herein according to a dosing regimen comprising a first 28-day cycle and subsequent 2 to 10 28-day cycles. In yet another embodiment, the method disclosed herein comprises administering the combination therapy disclosed herein according to a dosing regimen comprising a first 28-day cycle and subsequent 2 to 8 28-day cycles. In one embodiment of the method disclosed herein, the dosing regimen comprises a first 28-day cycle and subsequent 2 to 36, 2 to 30, 2 to 24, 2 to 18, 2 to 12, 2 to 10, 2 to 8, 2 to 6, or 2 to 4 28-day cycles.

[0136] This article provides further examples of methods for treating hormone receptor-positive and HER2-negative locally advanced or metastatic breast cancer.

[0137] In one embodiment, the efficacy of the combination is measured as a function of PFS. In one such embodiment, the patient's PFS is increased by 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, or more months compared to no treatment or SOC treatment. In one embodiment, PFS is measured after the first dose of the combination therapy disclosed herein for at least 64 months. In another embodiment, the efficacy is measured in relation to PFS in a biomarker-positive patient set (e.g., including the biomarker group described herein, including PIK3CA) compared to a biomarker-negative patient set.

[0138] In one embodiment, compared with no treatment or SOC treatment, treatment with combination therapy according to the methods provided herein increases a patient's OS by 3, 4, 5, 6, 7, 8, 9, 10, 15, 20, or more months. In one embodiment, treatment with combination therapy according to the methods provided herein increases a patient's ORR by an amount. In another embodiment, the relief efficacy is measured as a function of DOR comparable to no treatment or SOC treatment. In yet another embodiment, the relief efficacy is measured as a function of CBR comparable to no treatment or SOC treatment.

[0139] In another embodiment, after treatment with combination therapy according to the methods provided herein, the patient's TTP level is increased. In another embodiment, after treatment with combination therapy according to the methods provided herein, the patient's PFS level is increased. In one embodiment provided herein, after treatment with combination therapy according to the methods provided herein, the patient is diagnosed with CR. In one embodiment provided herein, after treatment with combination therapy according to the methods provided herein, the patient is diagnosed with PR. In one embodiment provided herein, after treatment with combination therapy according to the methods provided herein, the patient is diagnosed with SD.

[0140] In some of these embodiments, the patient has locally advanced or metastatic breast cancer (e.g., histologically or cytologically confirmed) that is not treatable by curative therapies (e.g., surgery or radiation therapy with curative intent).

[0141] In some embodiments, the patient experiences a disease exacerbation during adjuvant endocrine therapy or within 12 months after completion of adjuvant endocrine therapy (e.g., using an aromatase inhibitor or tamoxifen). Non-limiting examples of aromatase inhibitors include anastrozole, letrozole, and exemestane. In some embodiments, where a CDK4 / 6 inhibitor is included as part of neoadjuvant or adjuvant therapy, the patient's exacerbation event must have occurred > 12 months after completion of the CDK4 / 6 inhibitor portion of the neoadjuvant or adjuvant therapy.

[0142] In one embodiment of the method disclosed herein, the patient had been treated with one or more cancer therapies prior to administration of the combination therapy disclosed herein. In one embodiment of the method disclosed herein, the prior therapy comprised fulvestrant or letrozole and / or a CDK4 / 6 inhibitor (e.g., palbociclib, ribociclib, or abeciclib). In another embodiment, the patient disclosed herein had not previously been treated with fulvestrant or letrozole, a PI3K inhibitor, and / or a CDK4 / 6 inhibitor.

[0143] In one embodiment of the method disclosed herein, the patient has the breast cancer described herein that is resistant to one or more cancer therapies (e.g., CDK4 / 6 inhibitors, such as palbociclib, rebociclib, or abeciclib). In one embodiment of the method disclosed herein, resistance to cancer therapy includes recurrent or refractory cancer. Recurrence may refer to the reappearance of cancer at the original site or a new site after treatment. In one embodiment of the method disclosed herein, resistance to cancer therapy includes the progression of the cancer during treatment with anticancer therapy. In some embodiments of the method disclosed herein, resistance to cancer therapy includes cancer that does not produce remission to treatment. The cancer may be resistant at the start of treatment or may become resistant during treatment. In some embodiments of the method disclosed herein, the cancer is in an early or late stage.

[0144] Co-administration of GDC-0077 with a CDK4 / 6 inhibitor (e.g., palbociclib, ribociclib, or abeciclib) and an endocrine therapy (e.g., fulvestrant or letrozole) can prevent or delay the development of resistance in tumors (e.g., breast cancer) to a combination of CDK4 / 6 inhibitors (e.g., palbociclib, ribociclib, or abeciclib) and an endocrine therapy (e.g., fulvestrant or letrozole). Therefore, a method for preventing or delaying the development of resistance in tumors (e.g., breast cancer) to a therapy containing a CDK4 / 6 inhibitor (e.g., palbociclib, ribociclib, or abeciclib) is provided, comprising administering the combination therapy detailed herein. In some embodiments, a method for preventing or delaying the development of resistance in a tumor (e.g., breast cancer) to a therapy containing palbociclib is provided, comprising administering a combination therapy comprising GDC-0077, palbociclib, and fulvestrant, or a combination therapy comprising GDC-0077, palbociclib, and letrozole. In some embodiments, the combination therapy is administered according to any method as detailed herein.

[0145] In one embodiment, the patient disclosed herein had been pretreated with an aromatase inhibitor (e.g., anastrozole, letrozole, or exemestane) or tamoxifen prior to administration of the combination therapy disclosed herein. In one such embodiment, the patient relapsed during prior treatment with an aromatase inhibitor or tamoxifen or otherwise demonstrated disease progression following such administration. In one such embodiment, the relapse or disease progression was observed during the first 12 months of adjuvant endocrine therapy. In one embodiment, the prior treatment was with one or more aromatase inhibitors as disclosed herein. In another embodiment, the prior treatment was with tamoxifen. In yet another such embodiment, the prior treatment was for locally advanced or metastatic breast cancer. In one such embodiment, the patient disclosed herein had been pretreated with letrozole, tamoxifen, anastrozole, or exemestane. In yet another such embodiment, the patient disclosed herein had been pretreated with an aromatase inhibitor or tamoxifen for 3 to 6 years prior to administration of the combination therapy disclosed herein. In another such embodiment, the patient described herein had been pretreated with an aromatase inhibitor or tamoxifen for more than 6 years prior to administration of the combination therapy disclosed herein. In yet another embodiment, the patient described herein was a postmenopausal patient. In yet another embodiment, the patient described herein had at least one measurable lesion, such as that measurable by means of RECIST, for example.

[0146] In one embodiment of the method disclosed herein, prior to administration of the combination therapy disclosed herein, patients with hormone receptor-positive and HER2-negative locally advanced or metastatic breast cancer may have undergone surgical treatment such as, for example, breast-conserving surgery (i.e., mastectomy, which focuses on removing the primary tumor with margins) or more extensively (i.e., mastectomy, which aims to completely remove all breast tissue). In another embodiment, patients disclosed herein may undergo surgical treatment after treatment with the combination therapy disclosed herein.

[0147] Radiation therapy is typically administered postoperatively to the breast / chest wall and / or regional lymph nodes to kill any remaining microscopic cancer cells. In breast-conserving surgery, radiation is administered to the remaining breast tissue, and sometimes to regional lymph nodes (including axillary lymph nodes). In mastectomy, radiation may still be administered if there are factors predicting a higher risk of local recurrence. In some embodiments of the methods provided herein, patients with hormone receptor-positive and HER2-negative locally advanced or metastatic breast cancer may have already received radiation therapy prior to administration of the combination therapy disclosed herein. In other embodiments of the methods provided herein, patients with hormone receptor-positive and HER2-negative locally advanced or metastatic breast cancer may have already received radiation therapy after administration of the combination therapy disclosed herein.

[0148] In another embodiment, the patient had not been pretreated with a PI3K inhibitor. In yet another embodiment, the patient had not been pretreated with an mTOR inhibitor. In yet another embodiment, the patient had not been pretreated with an AKT inhibitor. In still another embodiment, the patient had not previously received cytotoxic chemotherapy for metastatic breast cancer. In yet another embodiment, the patient disclosed herein had not previously received SERD (estrogen receptor selective degrader) containing, for example, fulvestrant.

[0149] This article also provides methods for inhibiting tumor growth or causing tumor regression in patients disclosed herein by administering the combination therapies disclosed herein.

[0150] In one embodiment, this document provides a method for inducing or improving tumor regression in a patient disclosed herein by administering the combination therapy disclosed herein.

[0151] The development of combination therapies is challenging, including, for example, selecting agents for combination therapies that can lead to improved efficacy while maintaining acceptable toxicity. A specific challenge is the need to differentiate the incremental toxicity of the combination. In one embodiment of the methods disclosed herein, the combination therapies disclosed herein (e.g., GDC-0077, fulvestrant, and palbociclib) are administered using a dosing regimen that includes staggered dosing schedules. In one embodiment, the combination therapies disclosed herein (e.g., GDC-0077, fulvestrant, and palbociclib) are administered simultaneously over a 28-day cycle.

[0152] In one embodiment of the method provided herein, GDC-0077 is administered on each day of each 28-day cycle (QD), and palbociclib is administered on days 1 through 21 of each 28-day cycle (QD). In such embodiments, fulvestrant is administered as disclosed herein, such as on days 1 and 15 of the first 28-day cycle, and on day 1 of each subsequent 28-day cycle.

[0153] In one embodiment of the method provided herein, GDC-0077 and letrozole are each administered in a 28-day cycle QD, and palbociclib is administered in a QD from day 1 to day 21 of each 28-day cycle.

[0154] In some embodiments, the patient had adequate hematological and organ function within 14 days prior to the start of the study treatment.

[0155] Metformin can be administered to manage hyperglycemia in patients at risk of or prone to hyperglycemia (e.g., obese or prediabetic patients). Therefore, in some embodiments, a method is provided for treating a patient with PIK3CA-mutated, hormone receptor-positive, and HER2-negative locally advanced or metastatic breast cancer, comprising administering a combination therapy to the patient comprising GDC-0077, a CDK4 / 6 inhibitor (e.g., palbociclib, ribociclib, or abeciclib), and an endocrine therapy (e.g., fulvestrant or letrozole), wherein the patient has previously received metformin treatment. In some embodiments, the method comprises administering metformin, GDC-0077, palbociclib, and fulvestrant, wherein GDC-0077, palbociclib, and fulvestrant are administered according to any of the methods detailed herein. In some embodiments, the method comprises administering metformin, GDC-0077, palbociclib, and letrozole, wherein GDC-0077, palbociclib, and letrozole are administered according to any method detailed herein. In some of these embodiments, the dose or regimen of metformin is adjusted to reduce, stabilize, or eliminate hyperglycemia in the patient prior to administration of GDC-0077. In some of these embodiments, 500 mg to 2000 mg (e.g., 500 mg) of metformin is administered to the patient daily for approximately 15 days prior to administration of GDC-0077. In some of these embodiments, 500 mg to 2000 mg (e.g., 500 mg) of metformin is administered to the patient daily for approximately 15 days prior to administration of palbociclib and fulvestrant or letrozole, followed by administration of GDC-0077. In some of these embodiments, GDC-0077, palbociclib, and fulvestrant or letrozole are administered according to the dosing regimen detailed herein.

[0156] Biomarkers

[0157] Breast cancer is a heterogeneous disease with many distinct subtypes defined by molecular tags and a wide variety of mutation profiles. In one embodiment, a patient's PIK3CA / AKT1 / PTEN alteration status can be tested. In one embodiment, mutations in the phosphatase and tensin homolog (PTEN), loss of PTEN expression, phosphatidylinositol-4,5-bisphosphate 3-kinase catalytic subunit α (PIK3CA) mutation, protein kinase B α (AKT1) mutation, or a combination thereof can be tested in the patients disclosed herein. In one embodiment, the loss of PTEN expression is hemizygous or homozygous. In another embodiment, additional biomarkers in samples from the patients disclosed herein can be evaluated to identify factors that may be associated with the safety and efficacy of the study treatment.

[0158] In one embodiment of the methods disclosed herein, NGS, whole-genome sequencing (WGS), other methods, or combinations thereof, can be used to obtain DNA from blood samples and tumor tissues from patients disclosed herein. Such samples can be analyzed to identify germline (e.g., BRCA1 / 2) and somatic alterations that predict remission to the investigational drug, are associated with progression to a more severe disease state, are associated with acquired resistance to the investigational drug, or may increase knowledge and understanding of the biology of the disease. In another embodiment of the methods disclosed herein, the patients disclosed herein may have cancers characterized by activation of PI3K / Akt signaling, such as mutations in activated PIK3CA or AKT1 and alterations in PTEN, as provided herein. In another embodiment, the tumor status of PIK3CA / AKT1 / PTEN alterations will be determined using NGS testing (e.g., Foundation Medicine, Inc. [FMI]). Retrospective studies of the status of PIK3CA / AKT1 / PTEN alterations and remission measurements in archived tissues can be continued. The performance of the biomarkers (e.g., PTEN) described herein can be measured using techniques known in the art, such as, for example, immunohistochemistry (IHC).

[0159] Circulating tumor DNA (ctDNA) can be detected in the blood of cancer patients with epithelial carcinoma and can have diagnostic and therapeutic significance (Schwarzenbach et al. 2011). For example, mutated tumor cells can be obtained by isolating ctDNA (Maheswaran S et al. N Engl J Med 2008;359:366-77), and ctDNA has been used to monitor the effectiveness of treatment in melanoma (Shinozaki M et al. Clin Cancer Res 2007;13:2068-74). Blood samples from patients described in this article can be collected at screening, at the initial tumor assessment, and / or at the completion / early termination of follow-up of the study. In one embodiment, these samples are used to evaluate baseline oncogene alterations and to assess the likelihood of new alterations emerging after treatment with GDC-0077, CDK4 / 6 inhibitors (e.g., palbociclib, ribociclib, or abeciclib), and fulvestrant or letrozole.

[0160] Example

[0161] Abbreviations: AE, Adverse Event; AUC0–24, Area under the Concentration-Time Curve from 0 to 24 Hours; BMI, Body Mass Index; CDK4 / 6i, Cyclin-dependent Kinase 4 / 6 Inhibitor; CI, Confidence Interval; Cmax, Maximum Serum Concentration; CR, Complete Response; ctDNA, Circulating Tumor DNA; D, Day; ECOG, East Coast Cancer Clinical Research Collaboration; GMR, Geometric Ratio; HbA1c, Glycated Heme; HER2, Human Epidermal Growth Factor Receptor 2; MAF, Mutant Allele Frequency; MBC, Metastatic Breast Cancer; MTD, Maximum Tolerated Dose; NCI-CTCAE, National Cancer Institute Common Terminology Standard for Adverse Events; PD, Pharmacokinetics; PrD, Disease Progression; PIK3CA, Phosphatidylinositol-4,5-bisphosphate 3-kinase, Catalytic Subunit α; PK, Pharmacokinetics; PR, Partial Response; pts: Patient RECIST, Evaluation Criteria for Response in Solid Tumors. SD, disease stable; SLD, sum of longest diameters; TRAE, treatment-related adverse events.

[0162] Example 1: Efficacy of GDC-0077, palbociclib, and fulvestrant in xenograft mouse model

[0163] The efficacy of the drug alone and in combination with GDC-0077, palbociclib and fulvestrant was demonstrated in a xenograft model of MCF-7 (PIK3CA mutant E545K, ER+) breast cancer using female athymic nude mice.

[0164] Program:

[0165] 1 to 3 days before cell implantation, 0.36 mg estradiol pellets are implanted between the shoulder blades.

[0166] CR female NCr nu / nu mice were established and 1 x 10⁷ MCF7 tumor cells in 0% Matrigel were injected into the mammary fat pad.

[0167] The cell injection volume was 0.1 mL / mouse.

[0168] Monitor mice for signs of estrogen toxicity. Monitoring includes weekly bladder palpation for the first 3-4 weeks after pellet implantation. After 3-4 weeks, monitoring should be performed at least twice a week as signs of toxicity may appear. Monitoring consists of bladder palpation to determine if the bladder is enlarged. The bladder will be visible when it is enlarged. If the animal is unable to urinate on its own and its bladder is not visible, or if there is blood or sediment in the urine, it should be euthanized.

[0169] Age of start date: 8 to 10 weeks.

[0170] When the tumors reach an average size of 180 to 220 mm³, they are paired and treatment begins.

[0171] Weight: 5 / 2, then biwk to the end.

[0172] Caliper measurement: biwk to end

[0173] Immediately report any adverse reactions or deaths to the RM, SD, RD or site manager.

[0174] Euthanize any animal that shows a single observed weight loss of >30% or three consecutive measurements of weight loss of >25%.

[0175] In any group with a mean weight loss > 20% or a mortality rate > 10%, administration was discontinued. No individuals in that group were euthanized, and recovery was permitted. In groups with a weight loss > 20%, individuals who reached their individual weight loss endpoint were euthanized. When weight loss associated with group treatment returned to within 10% of original weight, administration may be restarted at a lower dose or with a less frequent dosing schedule. On an individual basis, exceptions may be made for untreated weight recovery percentages.

[0176] Endpoint TGD. Animals were monitored separately. The experimental endpoint was a tumor volume of 2000 mm3 or 45 days, whichever came first. Animals in remission could be followed up for a longer period. When the endpoint was reached, the animals were euthanized according to the SOP.

[0177] Preparation of Drug Delivery Solution

[0178] GDC-0077 Solution in 0.5% methylcellulose: Prepare 0.2% Tween 80 deionized water daily at room temperature and store at 4°C.

[0179] Palbociclib in 0.5% methylcellulose: Prepare 0.2% Tween 80 deionized water weekly at room temperature and store at 4°C.

[0180] Prepare a 10% ethanol solution of fulvestrant in corn oil weekly at room temperature and store at 4°C.

[0181] The medium used is 0.5% methylcellulose: 0.2% Tween 80 in deionized water.

[0182] Administration:

[0183] Before administration, allow the modifier to reach room temperature.

[0184] The dosage of GDC-0077 is determined by MTD.

[0185] Administer palbociclib, then fulvestrant, then GDC-0077 (immediately following each other). On days when fulvestrant has not been administered, administer palbociclib first, followed immediately by GDC-0077.

[0186] The administration volume of GDC-0077, palbociclib, and the median solution is 10 mL / kg (0.200 mL / 20 g mouse), and adjusted according to body weight.

[0187] The volume of fulvestrant administered was 0.2 mL / mouse, not adjusted for body weight.

[0188] Result

[0189] GDC-0077 and palbociclib were administered once daily via tube feeding, and fulvestrant was administered once weekly via subcutaneous injection (sc) at 200 mg / kg (5 mg / mouse). In one study, each mouse (N = 12) received 25 mg / kg (oral, QD) GDC-0077 (G) for 21 days, 50 mg / kg (oral, QD) palbociclib (P) for 21 days, and 200 mg / kg (sc, weekly) fulvestrant (F) for 3 weeks. The effects of each single agent (P, F, and G), dual combinations (P + F, G + F, and G + P), and triple combinations (G + P + F) are shown in Figure 1. Table 1 lists tumor growth inhibition (%TGI), CR, and PR. Results showed that GDC-0077 enhanced the efficacy of palbociclib and fulvestrant in a mouse model of MCF-7 PIK3CA mutant E545K ER+ breast cancer xenograft. The triple combination also showed more partial responses (PRs). All drug treatments and combination therapies were tolerable based on body weight.

[0190] Table 1. %TGI, CR, and PR in xenografts in MCF-7 mice (12 animals per group) Agent %TGI PR CR P 45 0 0 F 52 0 0 G 35 0 0 P+F 71 0 0 G+F 85 0 0 G+P 87 1 0 G+P+F 106 8 0

[0191] However, at a daily dose of 50 mg / kg of GDC-0077, the triple combination can produce toxicity, as shown by significant weight loss (Figure 2).

[0192] Example 2: GDC-0077 Dosage Escalation Study

[0193] The Phase I dose escalation study of daily oral GDC-0077 monotherapy and in combination with other therapies was conducted in patients with locally advanced or metastatic PIK3CA-mutated solid tumors.

[0194] Research Design

[0195] An open-label, phase I dose-escalation design using a 3+3 design.

[0196] GDC-0077 is administered orally at a dose of 6 mg, 9 mg, or 12 mg per day (QD).

[0197] The primary objective was to determine the maximum tolerated dose (MTD) and / or the recommended phase II dose (RP2D) and to assess the safety of GDC-0077 in patients with PIK3CA-mutated solid tumors.

[0198] Key eligibility criteria: PIK3CA mutation in tumor tissue or ctDNA; fasting blood glucose ≤ 140 mg / dL; HbA1c < 7%.

[0199] To evaluate single-dose pharmacokinetics (PK), frequent blood sampling was performed up to 48 hours after the initial dose on day 1 of cycle 1. Blood sampling was performed on day 15 of cycle 1 after daily dosing starting on day 8 of cycle 1 to evaluate steady-state PK.

[0200] RECIST v1.1 performs tumor assessments at screening and every 8 weeks to evaluate preliminary antitumor activity. Clinical benefit is defined as complete or partial remission, or disease stabilization lasting ≥ 24 weeks.

[0201] Before and during the study (2 weeks after daily GDC-0077 treatment), pharmacokinetic activity was assessed by immunohistochemistry (IHC) in tumor biopsies and in ctDNA samples (by FoundationACT) using FDG-PET scans.

[0202] Result

[0203] By the clinical cutoff, 20 patients had been recruited and treated with a single dose of GDC-0077. All patients were female with hormone receptor-positive, HER2-negative (HR+ / HER2-) breast cancer, except for one male patient with colorectal cancer. The median age was 65 years (41–77), and 11 patients (55%) had ECOG 0 at baseline. Overall, five patients (25%) were obese (BMI ≥ 30), and two patients (50%) in the 12 mg group were obese.

[0204] In metastatic cases, the median prior cancer treatment was 3 (1-12). Fifteen (75%) patients had previously received chemotherapy in metastatic cases.

[0205] The median treatment duration of GDC-0077 was 3.8 months (range 1.1-17.5), and the cumulative dose intensity of GDC-0077 was 97%.

[0206] All patients discontinued treatment due to disease progression (radiography or clinical presentation).

[0207] Results - Safety

[0208] Table 2 shows the most common adverse events (AEs) and treatment-related (TR) AEs.

[0209] Table 2. Overall, ≥20% of patients experienced adverse events. GDC-0077 6 mg (n=7) GDC-0077 9 mg (n=9) GDC-0077 12 mg (n=4) All patients (N=20) all Related all Related all Related all Related diarrhea 7 (100%) 3 (43%) 4 (44%) 3 (33%) 3 (75%) 2 (50%) 14 (70%) 8 (40%) High blood sugar 4 (57%) 4 (57%) 6 (67%) 6 (67%) 4 (100%) 4 (100%) 14 (70%) 14 (70%) nausea 2 (29%) 1 (14%) 5 (56%) 1 (11%) 4 (100%) 1 (25%) 11 (55%) 3 (15%) Vomit 2 (29%) 1 (14%) 5 (56%) 3 (33%) 2 (50%) - 9 (45%) 4 (20%) fatigue - - 4 (44%) 2 (22%) 2 (50%) 1 (25%) 6 (30%) 3 (15%) AST elevated 1 (14%) - 4 (44%) - - - 5 (25%) - constipate 1 (14%) 1 (14%) 2 (22%) 1 (11%) 2 (50%) - 5 (25%) 2 (10%) decreased appetite 2 (29%) 1 (14%) 3 (33%) 3 (33%) - - 5 (25%) 4 (20%) hyponatremia 1 (14%) - 2 (22%) 1 (11%) 2 (50%) 1 (25%) 5 (25%) 2 (10%) Thrombocytopenia 2 (29%) 1 (14%) 3 (33%) 1 (11%) - - 5 (25%) 2 (10%) stomach ache - - 2 (22%) 1 (11%) 2 (50%) - 4 (20%) 1 (5%) Baldness - - 4 (44%) 3 (33%) - - 4 (20%) 3 (15%) ALT elevation 1 (14%) - 3 (33%) - - - 4 (20%) - Alkaline phos. incr. - - 2 (22%) - 2 (50%) - 4 (20%) - Difficulty breathing 1 (14%) - 3 (33%) - - - 4 (20%) - hypophosphatemia - - 3 (33%) - 1 (25%) - 4 (20%) - Peripheral edema 1 (14%) - 3 (33%) 1 (11%) - - 4 (20%) 1 (5%) Stomatitis 1 1 (14%) 1 (14%) 3 (33%) 3 (33%) - - 4 (20%) 4 (20%) Blurred vision 2 (29%) 1 (14%) 1 (11%) - 1 (25%) 1 (25%) 4 (20%) 2 (10%) 1. Stomatitis group terminology = stomatitis, mucosal inflammation, oral ulcer, glossitis, lip ulcer, palatal ulcer, and tongue ulcer.

[0210] Two patients experienced dose-limiting toxicities at 12 mg (one had grade 4 hyperglycemia, and the other had grade 3 fatigue lasting 5 days). The MTD for GDC-0077 was established as 9 mg QD.

[0211] Grade ≥3 TRAE included hyperglycemia (4 cases, 20%), as well as lymphopenia, fatigue, nausea, weight loss, and weakness (1 case, 5%).

[0212] AEs resulted in dose reductions in 6 patients (30%; including 3 patients treated with a 12 mg dose, exceeding the MTD), and included hyperglycemia and nausea.

[0213] Hyperglycemia was the most common treatment-associated acute exacerbation (TRAE), which could be managed with oral antihyperglycemic agents (most commonly metformin in 11 patients). Stomatitis (including stomatitis, mucosal inflammation, oral ulcers, glossitis, lip ulcers, palatal ulcers, and tongue ulcers; all grade 1) was usually relieved by topical corticosteroid therapy (i.e., dexamethasone mouthwash). Rash (including rash, maculopapular rash, acneiform dermatitis, erythema, and generalized rash) occurred in 3 patients (15%) (1 unrelated grade 2, otherwise grade 1). No treatment-related serious gastrointestinal toxicities were reported (all treatment-related diarrheal events were grade 1-2). No colitis was reported (9 patients treated for ≥5 months in the study).

[0214] Results - Pharmacokinetics

[0215] Plasma exposure to GDC-0077 increased proportionally after single and multiple administrations.

[0216] The mean half-life (t1 / 2) after single administration of GDC-0077 was 18.1 hours.

[0217] With continuous once-daily administration, there was a cumulative effect of approximately 1.3 to 3.1 times, consistent with the observed t1 / 2 and dosing frequency.

[0218] After single administration and at steady state at MTD (9 mg), the PK variability of Cmax and AUC0-24 was low (%CV ~20%).

[0219] Results – Clinical Activity

[0220] Overall, partial response (PR) was observed in 5 patients (best overall response rate: 25%, all responders had at least 3 lines of prior metastasis therapy), and PR was confirmed in 4 patients (confirmed overall response rate: 20%).

[0221] Among 19 patients with measurable disease, the best overall response rate was 26% and the confirmed overall response rate was 21%.

[0222] The clinical benefit rate was 45% (9 out of 20 patients).

[0223] Single-agent antitumor activity is shown in Figure 3. p110α mutations: KIN = kinase domain (H1047, M1043); HEL = helical domain (E545, E542, Q546); Mul = multiple mutations; O = other: N345K.

[0224] Results – Pharmacodynamics

[0225] At all assessed dose levels, baseline and FDG-PET scans 2 weeks after daily GDC-0077 showed metabolic responses.

[0226] Decreased PI3K pathway activity was observed in paired tumor biopsies assessed by IHC for phosphoproteins.

[0227] Over time, the frequency of ctDNA PIK3CA mutant alleles was observed to decrease in most samples.

[0228] Conclusion

[0229] A single-dose escalation study of the oral p110α selective and mutagenic degradation inhibitor GDC-0077 elucidated manageable safety data and determined the MTD to be 9 mg once daily.

[0230] PK analysis showed a linear PK curve and supported daily dosing.

[0231] The antitumor activity showed promising preliminary results, with an overall response rate of 21% in cancer patients with PIK3CA mutations.

[0232] Pharmacokinetic regulation was observed in tumors by FDG-PET, in tumor biopsy sections by IHC, and in ctDNA kinetics.

[0233] Clinical Study of GDC-0077 / Pabociclib / Letrozole Combination

[0234] An open-label, phase I dose-escalation study of GDC-0077 alone, orally daily, and in combination with endocrine and targeted therapies is underway.

[0235] Research Design

[0236] Administer GDC-0077 6 mg or 9 mg orally daily (QD) in combination with letrozole (G+L) or GDC-0077 3 mg, 6 mg, or 9 mg in combination with palbociclib and letrozole (G+P+L).

[0237] Letrozole is administered orally at a dose of 2.5 mg once daily. Palbociclib is administered orally at a dose of 125 mg once daily from day 1 to day 21, followed by a 7-day break. Both are administered according to the dosing label.

[0238] Key eligibility criteria: PIK3CA mutation in tumor tissue or ctDNA; fasting blood glucose ≤ 140 mg / dL, HbA1c < 7%. To increase the dose, prior CDK4 / 6 inhibitors were prohibited (G+P+L group only), and one prior metastatic chemotherapy was permitted (both groups).

[0239] Antitumor activity was evaluated based on investigator assessment using RECIST v1.1 at screening and every 8 weeks. Clinical benefit rate (CBR) was defined as complete or partial response, or disease stabilization lasting ≥ 24 weeks.

[0240] Before and during the study (2 weeks after daily GDC-0077 treatment), pharmacokinetic activity was assessed by immunohistochemistry (IHC) in tumor biopsies and in ctDNA samples (by FoundationACT).

[0241] Result

[0242] As of the clinical cutoff, 37 patients were recruited to G+L and 33 patients were recruited to G+P+L.

[0243] All patients were postmenopausal women with HR+ / HER2 breast cancer. The median age was 58 years (range 43-79) for G+L and 57 years (range 37-80) for G+P+L. Of the patients with an ECOG of 0, 25 (68%) were in G+L and 20 (61%) were in G+P+L. Eight patients recruited as G+L (22%) and 10 patients recruited as G+P+L (30%) had a BMI ≥ 30 (obese).

[0244] In metastatic cases, the median number of prior cancer treatments was 3 (0-11) in G+L and 2 (0-4) in G+P+L.

[0245] Number of patients treated with prior chemotherapy in cases of metastasis: 18 (49%) in the G+L group and 14 (42%) in the G+P+L group.

[0246] The median duration of GDC-0077 treatment in the G+L group was 3.7 months (range 0.2–17.3), and the median duration of treatment in the G+P+L group was 11.5 months (range 1.3–23.9). The cumulative dose intensity of GDC-0077 was 98% in both groups. The cumulative dose intensity of letrozole was 100% in the G+L group and 99% in the G+P+L group. The cumulative dose intensity of palbociclib was 86% in the G+P+L group.

[0247] Of the 70 patients, 51 discontinued treatment primarily due to disease exacerbation; 1 case was attributed to grade 3 hyperglycemia in the G+P+L group (no patients in the G+L group discontinued treatment due to AE).

[0248] Results - Safety

[0249] Table 3 shows the most common treatment-related (TR) AEs and grade 3-4 TRAEs for G+L, while Table 4 shows the AEs for G+P+L.

[0250] Table 3. TRAE and corresponding grade 3-4 TRAE in >10% of patients with GDC-0077 + letrozole (N = 37) All levels Level 3 to 4 Total number of patients with ≥1 AE 35 (95%) 11 (30%) High blood sugar 25 (68%) 7 (19%) nausea 14 (38%) - Stomatitis 1 11 (30%) - diarrhea 10 (27%) - Taste disorder 9 (24%) - fatigue 8 (22%) 2 (5%) decreased appetite 7 (19%) - Dry mouth 6 (16%) - Vomit 5 (14%) - Joint pain 4 (11%) - 1. Stomatitis group terminology = stomatitis, mucosal inflammation, oral ulcer, glossitis, lip ulcer, palatal ulcer, and tongue ulcer.

[0251] Table 4. TRAE and corresponding grade 3-4 TRAE for >10% of patients with GDC-0077 + palbociclib + letrozole (N = 33) All levels Level 3 to 4 Total number of patients with ≥1 AE 33 (100%) 27 (82%) Neutropenia 26 (79%) 21 (64%) Stomatitis 1 22 (67%) 1 (3%) High blood sugar 18 (55%) 6 (18%) anemia 17 (52%) 1 (3%) diarrhea 15 (46%) - Baldness 14 (43%) - nausea 13 (39%) - Thrombocytopenia 13 (39%) 2 (6%) decreased appetite 12 (36%) - Taste disorder 9 (27%) - rash 2 9 (27%) - Vomit 8 (24%) - muscle spasms 7 (21%) - Dry mouth 7 (21%) 1 (3%) powerless 6 (18%) - Leukopenia 6 (18%) 3 (9%) fatigue 4 (12%) - stomach ache 4 (12%) - weight loss 4 (12%) - Peripheral edema 4 (12%) - Dry skin 4 (12%) - GERD 4 (12%) - Lymphopenia 4 (12%) 3 (9%) 1. Stomatitis group terminology = stomatitis, mucosal inflammation, oral ulcers, glossitis, lip ulcers, palatal ulcers, and tongue ulcers. 2. Rash group terminology = rash, maculopapular rash, acneiform dermatitis, erythema, and generalized rash.

[0252] No grade 4 TRAEs were reported in the G+L group; grade 4 TRAEs in the G+P+L group included neutropenia (6 patients, 18%) and hypophosphatemia (1 patient, 3%).

[0253] No dose-limiting toxicities were reported in any combination of GDC-0077 at doses up to 9 mg QD.

[0254] Hyperglycemia can be managed with oral antihyperglycemic agents. It resulted in dose interruption of GDC-0077 in 9 (24%) patients and dose reduction of GDC-0077 in 2 (5%) patients in the G+L group, and in 8 (24%) patients and 1 (3%) patients in the G+P+L group.

[0255] Neutropenia was similar to data published in studies using palbociclib plus endocrine therapy (Cristofanilli et al., Lancet Oncol 2016). It resulted in palbociclib dose interruption in 10 (30%) patients and palbociclib dose reduction in 12 (36%) patients.

[0256] Stomatitis (including stomatitis, mucosal inflammation, oral ulcers, glossitis, lip ulcers, palate ulcers, and tongue ulcers) can be relieved by dexamethasone mouthwash.

[0257] In the G + L group, 4 patients (11%) developed rashes (including rashes, maculopapular rash, acneiform dermatitis, erythema, and generalized rash) (1 patient was associated [3%]); in the G + P + L group, 11 patients (33%) developed rashes (9 patients were associated [27%]). All were grade 1.

[0258] Results - Clinical Activity

[0259] In the G+L group, 6 patients reported PR (best overall response rate: 16%), 3 patients had confirmed PR (confirmed ORR: 8%), and 13 patients had CBR (35%) (Figure 4). *p110α mutations: KIN = kinase domain (H1047, M1043); HEL = helical domain (E545, E542, Q546); Mul = multiple mutations; O = other: N345K. **Previous AI = previous aromatase inhibitor; A = adjuvant; M = metastatic status; B = both adjuvant and metastatic. Purple squares indicate treatment > 6 months.

[0260] Among 31 patients with measurable disease, the best overall response rate was 19%, and the confirmed ORR was 10% (1 patient did not have a post-baseline tumor assessment).

[0261] In the G+ P+L group, 15 patients reported PR (best overall response rate: 46%), 13 patients had confirmed PR (confirmed ORR: 39%), and 26 patients (79%) had CBR (Figure 5). *p110α mutations: KIN = kinase domain (H1047, M1043); HEL = helical domain (E545, E542, Q546); Mul = multiple mutations; O = other: N345K. **Previous AI = previous aromatase inhibitor; A = adjuvant; M = metastatic status; B = both adjuvant and metastatic. Purple squares indicate treatment > 6 months.

[0262] Among 25 patients with measurable disease, the best overall response rate was 60%, and the confirmed ORR was 52%.

[0263] Results-Pharmacokinetics

[0264] Preliminary results indicate that plasma exposure to GDC-0077 was similar between the single-dose and combination groups in this study.

[0265] Similarly, the pharmacokinetics of palbociclib and letrozole administered in combination with GDC-0077 are comparable to the single-dose PK of these agents as reported in the literature.

[0266] In this study, there were no drug interactions between GDC-0077 and its concomitant medications (palbociclib and letrozole).

[0267] Results-Pharmacodynamics

[0268] Strong downregulation of PD in PI3K pathway effectors (pAKT, pS6) was observed in paired tumor biopsies.

[0269] In most available samples, the frequency of the PIK3CA mutant allele via ctDNA decreased between day 1 of cycle 1 and day 15 of cycle 1.

[0270] Conclusion

[0271] This Phase Ib study of GDC-0077 in combination with letrozole, with or without palbociclib, elucidates manageable safety data for the combination of a single dose of GDC-0077 at a Phase II dose of 9 mg with letrozole and palbociclib at standard doses.

[0272] When used in combination, no PK DDI was observed for GDC-0077, palbociclib or letrozole compared to single-agent PK.

[0273] Promising preliminary antitumor activity was observed at doses of 3 mg, 6 mg, and 9 mg of GDC-0077, with an ORR of 10% in the G+L group and 52% in the G+P+L group in both combinations.

[0274] Pharmacokinetic regulation was observed in tumor biopsy sections and in ctDNA kinetics by IHC.

[0275] Case 4: Clinical study of the GDC-0077 / fulvestrant combination

[0276] An open-label, phase I / Ib study of daily oral GDC-0077 in combination with fulvestrant is underway.

[0277] Research Design

[0278] GDC-0077 is administered orally at a dose of 9 mg once daily on days 1 through 28 of each 28-day cycle. On days 1 and 15 of cycle 1, and on day 1 of each subsequent cycle, fulvestrant (F) is administered intramuscularly at a dose of 500 mg until intolerable toxicity or disease exacerbation occurs.

[0279] Safety (NCI-CTCAE v4), pharmacokinetic (PK), and preliminary antitumor activity (clinical benefit rate [CBR]: RECIST v1.1 disease stability ≥ 24 weeks, partial remission [PR], or complete remission) were assessed. The effect of a standard high-fat diet on the PK of G was evaluated at single doses and in a stable state. Relevant communication and pharmacodynamic (PD) biomarkers were assessed using circulating tumor (ct) DNA samples.

[0280] Result

[0281] By the clinical cutoff, 20 patients were recruited to the food effects portion of the G+F group.

[0282] All patients were postmenopausal women with HR+ / HER2 breast cancer. The median age was 54.5 years (range: 31–85); 17 patients (85%) had ECOG 0; seven patients (35%) had BMI ≥ 30 kg / m2 and / or HbA1c ≥ 5.7% (the required eligibility criterion HbA1c < 7%); 15 patients (75%) had ≥ 2 prior lines of treatment for metastatic breast cancer; and nine patients (45%) had previously been treated with a prior chemotherapy regimen in metastatic cases.

[0283] Safety

[0284] Among the 20 patients in this cutoff, the median duration of GDC-0077 treatment was 5.9 months (range 1.7–17.8); the cumulative dose intensity was 98%. Three patients (15%) had dose reductions due to adverse events (AEs).

[0285] The most common treatment-related (TR) adverse events (≥4 patients, 20%) were hyperglycemia (11, 55%), diarrhea (10, 50%), stomatitis (group terminology: stomatitis, mucosal inflammation, and oral ulcers; 9, 45%), nausea (8, 40%), decreased appetite (7, 35%), indigestion, fatigue, and muscle cramps (4 cases each, 20%).

[0286] TRAE of grade ≥ 3 included hyperglycemia, nausea, lymphopenia, hyperamylasemia, and hyperlipidemia (1 case each, 5%).

[0287] Pharmacokinetics

[0288] The pharmacokinetic (PK) profile of GDC-0077 in combination with fulvestrant is similar to that of the single-dose PK profile. Comparable GDC-0077 exposures (Cmax and AUC 0–24) were observed after administration in either fasting or fed states.

[0289] Clinical activity

[0290] Seventeen patients (85%) discontinued treatment due to radiography / clinical disease progression. Overall, 5 out of 14 patients with measurable disease achieved partial response (PR) (36%; 2 had received prior F; 4 had received prior CDK4 / 6i), of whom 2 (14%) achieved confirmed PR (Figure 6). The clinical benefit rate (CBR) was 60% (12 out of 20 patients).

[0291] Pharmacodynamics

[0292] Most patients showed a reduced frequency of the ctDNA PIK3CA mutation allele during treatment (paired ctDNA data not shown).

[0293] Conclusion

[0294] GDC-0077, in combination with fulvestrant, elucidated manageable safety data, similar to those of GDC-0077 alone, including pharmacokinetic (PK), preliminary antitumor activity, and PD regulation of PIK3CA mutant allele frequency in ctDNA. The presence of food had no significant effect on the rate or extent of GDC-0077 uptake, either alone or at a steady state.

[0295] Case 5: Phase 1 Clinical Study of the Iffalici / Papocinil / Flavestrant Combination

[0296] A Phase I / Ib study (NCT03006172) is underway in breast cancer patients with HR+ / HER2–, PIK3CA mutations using sefliximab (GDC-0077) alone or in combination with endocrine therapy ± palbociclib.

[0297] Research Design

[0298] In a 28-day cycle, 9 mg of sefliximab orally once daily + 125 mg of palbociclib for 21 / 28 days + 500 mg of fulvestrant intramuscularly on day 1 (and on day 15 of cycle 1) was administered in groups E and F until intolerable toxicity or disease progression.

[0299] In group F, patients were obese and / or prediabetic (body mass index ≥30 kg / m2 and / or heme A1c ≥5.7%). Before starting levamisole on day 15 of cycle 1, instead of day 1 as in group E, patients also received metformin ≤2000 mg daily, starting with 500 mg on day 1 of cycle 1.

[0300] Other key eligibility criteria include premenopausal / postmenopausal status, PIK3CA-mutated tumors as determined by local or central oncology testing, East Coast Cancer Clinical Research Cooperative (ECOG) performance status of 0 to 1, no prior PI3K or CDK4 / 6 inhibitor (CDK4 / 6i) therapy, and ≤1 prior chemotherapy session for Group E (no restrictions on prior CDK4 / 6i therapy or chemotherapy for Group F). Patients requiring medical treatment or with diabetes or heme A1c > 7% are excluded.

[0301] The frequency of PIK3CA mutant alleles was assessed in circulating tumor (ct) DNA from serial plasma collections using FoundationACT™ (Cambridge, MA).

[0302] Patient

[0303] By the clinical cutoff, 36 patients had been recruited: 20 in group E and 16 in group F. Recruitment for group F is ongoing. Baseline characteristics are shown in Table 5.

[0304] Table 5. Patient characteristics and treatment exposure Group E (n = 20) Group F (n = 16) Median age, in years (range) 55 (33–73) 65 (33–73) Median body mass index, kg / m 2 (scope) 25 (19.2-38.0) 33 (28.4-42.1) ECOG Daily Fitness Status 0, n (%) 10 (50%) 8 (50%) ≥2 previous treatments against mBC, n (%) 5 (25%) 13 (81%) Previously, fulvestrant, n (%) 3 (15%) 12 (75%) Previous CDK4 / 6 inhibitors, n (%) 0 10 (63%) Median duration of sefliximab treatment, in months (range). 6.8 (1.1-17.7) 6.3 (1.2-15.3) Median cumulative sefliximab dose intensity 93% 91% Median cumulative palbociclib dose intensity 86% 95% Median cumulative fulvestrant dose intensity 100% 100%

[0305] Sixteen patients (44%) discontinued treatment: 14 due to worsening of radiographic disease (5 in group E, 9 in group F); one due to an adverse event (AE; in group F, treatment-related grade 2 lipoitis); and one withdrew (group F).

[0306] Safety

[0307] Grade 1 Rash (group terminology, defined as: rash, maculopapular rash, acneiform dermatitis) There were 2 reported cases (10%) in group E and 1 reported case (6.3%) in group F.

[0308] Hyperglycemia was managed with hypoglycemic agents in eight patients (40%) in group E and nine patients (56%) in group F (excluding metformin), and sefliximab dose adjustment was required in five patients (25%) in group E and nine patients (56%) in group F. Sefliximab dose reduction was required in three patients (19%) in group F (none in group E). Despite prior treatment with metformin in obese and / or prediabetic patients, grade 3 to 4 hyperglycemia was observed in seven patients (44%) in group F (Table 6).

[0309] In a report on stomatitis (group terminology), 67% (24 / 36) of patients in both groups were managed with dexamethasone mouthwash in most cases (in most cases as treatment rather than prevention).

[0310] Neutropenia was managed with palbociclib dose adjustment (interruption and / or reduction), in 12 patients (60%) in group E and two patients (13%) in group F. In group E, three patients (15%) required palbociclib dose reduction (none in group F).

[0311] Neither group reported level 5 AE.

[0312] Table 6. ≥4 patients in both groups with treatment-related adverse events (excluding metformin-related ones), and corresponding treatment-related grade 3 to 4 adverse events. Group E (n = 20) Group F (n = 16) All levels Level 3 to 4 All levels Level 3 to 4 Total number of patients with ≥1 AE (%) 20 (100%) 16 (80%) 14 (88%) 12 (75%) Neutropenia 17 (85%) 13 (65%) 9 (56%) 9 (56%) Stomatitis* 16 (80%) 2 (10%) 8 (50%) 0 High blood sugar 12 (60%) 3 (15%) 11 (69%) 7 (44%) diarrhea 9 (45%) 1 (5%) 8 (50%) 0 Thrombocytopenia † 9 (45%) 4 (20%) 3 (19%) 1 (6%) anemia 7 (35%) 1 (5%) 4 (25%) 2 (13%) nausea 5 (25%) 0 8 (50%) 0 decreased appetite 5 (25%) 0 4 (25%) 0 fatigue 5 (25%) 0 3 (19%) 1 (6%) Baldness 4 (20%) 0 3 (19%) 0 powerless 4 (20%) 0 0 0 Blurred vision 0 0 4 (25%) 0 indigestion 0 0 4 (25%) 0 * Stomatitis (group term) is defined as: glossitis, mucositis, inflammation of the mucous membranes, oral ulcers, and lip ulcers. † Thrombocytopenia (group term) is defined as: thrombocytopenia, a decrease in platelet count.

[0313] Clinical Activity

[0314] Figures 7 and 8 show waterfall plots of antitumor activity in groups E and F, respectively. Overall, among patients with measurable disease: in group E, six out of 15 (40%) achieved partial remission (PR); in group F, two out of 15 patients (13%) achieved PR (all had previously received fulvestrant). All were confirmed PRs. The clinical benefit rate (defined as disease stability ≥24 weeks, PR, or complete remission [CR]) was 58% (21 out of 36 patients: 12 in group E; nine in group F). In group E, one patient with only evaluable disease at baseline achieved CR.

[0315] Pharmacokinetics

[0316] The pharmacokinetics of ivermectin combined with palbociclib plus fulvestrant are similar to those of ivermectin alone.

[0317] There were no drug interactions between levamisole and concomitant therapies (palbociclib and fulvestrant [and metformin]).

[0318] Pharmacodynamics

[0319] Data on the frequency of PIK3CA mutation alleles from ctDNA analysis are limited; however, over time, a decrease in the frequency of PIK3CA mutation alleles has been observed in some patients who have experienced disease stabilization or PR.

[0320] Conclusion

[0321] This Phase I / Ib study elucidated manageable safety data when combining the recommended single-dose dose of 9 mg efliximab with standard-dose palbociclib + fulvestrant, with no unexpected safety signals and pharmacokinetics similar to efliximab alone. Hyperglycemia was common in obese and / or prediabetic patients recruited to group F, despite initiation of metformin prior to efliximab.

[0322] Encouraging preliminary antitumor activity was observed in group E, with a remission rate of 40% (compared to 13% in group F). Limited data were available on the regulatory frequency of the PIK3CA mutant allele.

[0323] Case 6: Phase 3 Clinical Study of the Combination of Iffulix / Papocinil / Flvestrant

[0324] A multicenter, international, phase III randomized, double-blind, placebo-controlled study was designed to evaluate the efficacy, safety, and pharmacokinetics of epfuracetam (GDC-0077) in combination with palbociclib and fulvestrant compared with placebo in patients with PIK3CA-mutated, hormone receptor (HR)-positive, HER2-negative locally advanced or malignant breast cancer whose disease has progressed during treatment or within 12 months after completion of adjuvant endocrine therapy and who have not previously received systemic therapy for metastatic disease.

[0325] Group and Intervention

[0326] Experimental Group: GDC-0077 + Palbociclib + Fluvestralcone

[0327] Participants received: (a) oral GDC-0077 on days 1 to 28 of each 28-day cycle; (b) oral palbociclib on days 1 to 21 of each 28-day cycle; and (c) intramuscular (IM) fulvestrant approximately every 4 weeks.

[0328] Placebo control group: Placebo + Palbociclib + Fulvestrant

[0329] Participants received: (a) oral placebo on days 1 to 28 of each 28-day cycle; (b) oral palbociclib on days 1 to 21 of each 28-day cycle; and (c) intramuscular (IM) fulvestrant approximately every 4 weeks.

[0330] Result Measurement

[0331] Main Result Measurement:

[0332] 1. Disease-free survival (PFS) [Time frame: from randomization to the first occurrence of disease progression or death from any cause, whichever comes first (up to 6 years)]

[0333] Secondary result measurement:

[0334] 2. Objective Response Rate (ORR) [Timeframe: Up to 6 years]

[0335] 3. Best Overall Remission Rate (BOR) [Timeframe: Up to 6 years]

[0336] 4. Duration of Remission (DOR) [Timeframe: From the first occurrence of CR or PR to the first occurrence of disease exacerbation from any cause or death, whichever comes first (up to 6 years)]

[0337] 5. Clinical Benefit Rate (CBR) [Timeframe: Up to 6 years]

[0338] 6. Total Survival (OS) [Timeframe: From randomization to death from any cause (up to 6 years)]

[0339] 7. Time to Pain Worsening (TTD) [Timeframe: Treatment: Day 1 of cycles 1 to 3, then Day 1 of every other cycle until treatment ends. Post-treatment: Every 8 weeks for 2 years, then every 12 weeks until the end of the study (up to 6 years)]

[0340] 8. TTD in physiological function [Time frame: Treatment: Day 1 of cycles 1 to 3, then Day 1 of every other cycle until treatment ends. Post-treatment: Once every 8 weeks for 2 years, then once every 12 weeks until the end of the study (up to 6 years)]

[0341] 9. TTD in the role function [Time frame: Healing: Day 1 of cycles 1 to 3, then Day 1 of every other cycle until healing ends. Post-healing: Once every 8 weeks for 2 years, then once every 12 weeks until the research ends (reaching 6 years)]

[0342] 10. TTD in overall health condition [Time frame: Treatment: Day 1 of cycles 1 to 3, then Day 1 of every other cycle until treatment ends. Post-treatment: Every 8 weeks for 2 years, then every 12 weeks until the end of the study (up to 6 years)]

[0343] 11. Percentage of adverse events among participants [Time frame: from randomization to study end (up to 6 years)]

[0344] 12. Plasma concentration of GDC-0077 [Time frame: predetermined interval from baseline to end of study (up to 6 years)]

[0345] 13. Palbociclib plasma concentrations [Time frame: predetermined interval from baseline to end of study (up to 6 years)]

[0346] 14. Plasma concentrations of fulvestrant [Time frame: predetermined interval from baseline to the end of the study (up to 6 years)]

[0347] Competency

[0348] In one embodiment of this study, patients aged 18 years or older were included; all sexes were accepted (not based on sex). Healthy volunteers were not accepted. The inclusion and exclusion criteria for the target population are as follows.

[0349] Inclusion Criteria • Diagnosed HR+ / HER2- breast cancer • Metastatic or locally advanced disease untreatable by curative therapy • Disease progression during adjuvant endocrine therapy or within 12 months after completion of adjuvant endocrine therapy and use of aromatase inhibitors or tamoxifen • If premenopausal / or perimenopausal, received LHRH agonist therapy for at least 2 weeks prior to Day 1 of Cycle 1 • Confirmed adequacy of biomarkers (detection of a specified mutation in PIK3CA via a designated test) • Consent to provide a fresh or archived tumor tissue sample • Measurable disease according to the Solid Tumor Efficacy Evaluation Criteria, version 1.1; even if considered measurable “bone-only” disease, it does not qualify • US East Coast Cancer Clinical Research Collaboration performance status of 0 or 1 • Life expectancy > 6 months • Adequate hematologic and organ function within 14 days prior to the start of study treatment

[0350] Exclusion Criteria • Metaplastic breast cancer • History of leptomeningeal disease or carcinomatous meningitis • Any prior systemic therapy for metastatic breast cancer • Prior treatment with fulvestrant or any selective estrogen receptor degrader • Prior treatment with any PI3K, AKT, or mTOR inhibitor, or any agent whose mechanism of action is to inhibit the PI3K-AKT-mTOR pathway • Type 2 diabetes requiring ongoing systemic therapy at the time of study; or any history of type 1 diabetes • Known and untreated or active CNS metastases. Eligible candidates include: a history of treated CNS metastases; active inflammation or infection of either eye, or any eye condition requiring surgery during the study period; symptomatic active lung disease requiring daily supplemental oxygen; a history of inflammatory bowel disease or active bowel inflammation; anticancer therapy within 2 weeks prior to study entry; study drug within 4 weeks prior to randomization; prior radiation therapy to ≥25% of bone marrow or hematopoietic stem cell or bone marrow transplantation; chronic corticosteroid therapy or immunosuppressants; pregnancy, breastfeeding, or breastfeeding, or planning to become pregnant (during the study period or within 60 days after the final dose of study drug); major surgery or major trauma within 28 days (before Day 1 of Cycle 1).

[0351] Another embodiment A

[0352] Example A1. A combination for treating PIK3CA-mutated, hormone receptor-positive and HER2-negative locally advanced or metastatic breast cancer, wherein the combination comprises: (i) efliximab; (ii) palbociclib; and (iii) fulvestrant, and wherein the combination is administered over a 28-day cycle.

[0353] Example A2. A combination for treating PIK3CA-mutated, hormone receptor-positive, and HER2-negative locally advanced or metastatic breast cancer, wherein the combination is administered as a combination therapy comprising: a. administration of efliximab via QD on days 1 to 28 of the first 28-day cycle; b. administration of palbociclib via QD on days 1 to 21 of the first 28-day cycle; and c. administration of fulvestrant on days 1 and 15 of the first 28-day cycle.

[0354] Example A3. A combination of uses according to Example A2, wherein the dosing regimen further comprises one or more additional 28-day cycles, the cycle comprising: a. administration of efliximab on days 1 to 28 of each additional 28-day cycle; b. administration of palbociclib on days 1 to 21 of each additional 28-day cycle; and c. administration of fulvestrant on day 1 of each additional 28-day cycle.

[0355] Example A4. A combination of uses according to any one of Examples A1 to A3, wherein sefliximab is administered in an amount of 9 mg.

[0356] Example A5. A combination of uses according to Example A4, wherein epoxetine is administered orally in a dose of 9 mg.

[0357] Example A6. A combination of uses according to any one of Examples A1 to A5, wherein palbociclib is administered orally in a dose of 125 mg in capsules or tablets.

[0358] Example A7. A combination of uses according to any one of Examples A1 to A6, wherein fulvestrant is administered by intramuscular (IM) infusion at a dose of 500 mg.

[0359] Example A8. A combination for treating PIK3CA-mutated, hormone receptor-positive and HER2-negative locally advanced or metastatic breast cancer, wherein the combination comprises: (i) efliximab; (ii) palbociclib; and (iii) letrozole, and wherein the combination therapy is administered over a 28-day cycle.

[0360] Example A9. A combination for treating PIK3CA-mutated, hormone receptor-positive, and HER2-negative locally advanced or metastatic breast cancer, wherein the combination is administered as a combination therapy comprising: a. administration of efliximab via QD on days 1 to 28 of the first 28-day cycle; b. administration of palbociclib via QD on days 1 to 21 of the first 28-day cycle; and c. administration of letrozole via QD on days 1 to 28 of the first 28-day cycle.

[0361] Example A10. A combination of uses according to Example A9, wherein the dosing regimen further comprises one or more additional 28-day cycles, each cycle comprising: a. administration of efliximab on days 1 to 28 of each additional 28-day cycle; b. administration of palbociclib on days 1 to 21 of each additional 28-day cycle; and c. administration of letrozole on days 1 to 28 of each additional 28-day cycle.

[0362] Example A11. A combination of uses according to any one of Examples A8 to A10, wherein succinate is administered in an amount of 3 mg, 6 mg or 9 mg.

[0363] Example A12. A combination of uses according to Example A11, wherein sefliximab is administered in an amount of 9 mg.

[0364] Example A13. A combination of uses according to Example A12, wherein sefliximab is administered orally in a dose of 9 mg.

[0365] Example A14. A combination of uses according to any one of Examples A8 to A13, wherein palbociclib is administered orally in a dose of 125 mg in capsules or tablets.

[0366] Example A15. A combination of uses according to any one of Examples A8 to A14, wherein letrozole is administered orally in a dose of 2.5 mg.

[0367] Example A16. A combination of uses according to any one of Examples A1 to A15 for inhibiting tumor growth or producing / increasing tumor regression in patients with PIK3CA-mutated, hormone receptor-positive and HER2-negative locally advanced or metastatic breast cancer.

[0368] Example A17. A combination of uses according to any one of Examples A1 to A16, wherein the patient suffers from locally advanced or metastatic breast cancer that is not treatable.

[0369] Example A18. A combination of uses according to any one of Examples A1 to A17, wherein the patient experiences disease exacerbation during or within 12 months after completion of adjuvant endocrine therapy with aromatase inhibitors or tamoxifen.

[0370] Example A19. A combination of uses according to any one of Examples A1 to A18, wherein the patient has adequate hematological and organ function within 14 days prior to the start of the study treatment.

[0371] Example A20. A combination of uses according to any one of Examples A1 to A19, wherein the patient is a postmenopausal patient.

[0372] Example A21. A combination of uses according to any one of Examples A1 to A20 for preventing or delaying the development of resistance in breast cancer to therapies containing palbociclib.

[0373] Another embodiment B

[0374] Example B1. Use of a combination of medicines for treating PIK3CA-mutated, hormone receptor-positive and HER2-negative locally advanced or metastatic breast cancer, wherein the combination comprises: (i) efliximab; (ii) palbociclib; and (iii) fulvestrant, and wherein the combination therapy is administered over a 28-day cycle.

[0375] Example B2. Use of a combination of medicines for treating PIK3CA-mutated, hormone receptor-positive, and HER2-negative locally advanced or metastatic breast cancer, wherein the combination is administered as a combination therapy comprising: a. administration of efliximab via QD on days 1 to 28 of the first 28-day cycle; b. administration of palbociclib via QD on days 1 to 21 of the first 28-day cycle; and c. administration of fulvestrant on days 1 and 15 of the first 28-day cycle.

[0376] Example B3. As used in Example B2, wherein the dosing regimen further comprises one or more additional 28-day cycles, each cycle comprising: a. administration of efliximab on days 1 to 28 of each additional 28-day cycle; b. administration of palbociclib on days 1 to 21 of each additional 28-day cycle; and c. administration of fulvestrant on day 1 of each additional 28-day cycle.

[0377] Example B4. Used as in any of Examples B1 to B3, wherein sefliximab is administered in a dose of 9 mg.

[0378] Example B5. As used in Example B4, wherein sefliximab is administered orally in a dose of 9 mg.

[0379] Example B6. The use as described in any of Examples B1 to B5, wherein palbociclib is administered orally in a dose of 125 mg in capsules or tablets.

[0380] Example B7. Used as in any of Examples B1 to B6, wherein fulvestrant is administered by intramuscular (IM) infusion at a dose of 500 mg.

[0381] Example B8. Use of a combination of medicines for treating PIK3CA-mutated, hormone receptor-positive and HER2-negative locally advanced or metastatic breast cancer, wherein the combination comprises: (i) epfuliximab; (ii) palbociclib; and (iii) letrozole, and wherein the combination is administered over a 28-day cycle.

[0382] Example B9. Use of a combination of medicines for treating PIK3CA-mutated, hormone receptor-positive, and HER2-negative locally advanced or metastatic breast cancer, wherein the combination is administered as a combination therapy comprising: a. administration of efliximab via QD on days 1 to 28 of the first 28-day cycle; b. administration of palbociclib via QD on days 1 to 21 of the first 28-day cycle; and c. administration of letrozole via QD on days 1 to 28 of the first 28-day cycle.

[0383] Example B10. As used in Example B9, wherein the dosing regimen further comprises one or more additional 28-day cycles, each cycle comprising: a. administration of efliximab on days 1 to 28 of each additional 28-day cycle; b. administration of palbociclib on days 1 to 21 of each additional 28-day cycle; and c. administration of letrozole on days 1 to 28 of each additional 28-day cycle.

[0384] Example B11. As used in any of Examples B8 to B10, wherein epoxetine is administered in an amount of 3 mg, 6 mg or 9 mg.

[0385] Example B12. Used as in Example B11, wherein sefliximab is administered in an amount of 9 mg.

[0386] Example B13. As used in Example B12, wherein sefliximab is administered orally in a dose of 9 mg.

[0387] Example B14. Used as in any of Examples B8 to B13, wherein palbociclib is administered orally in a dose of 125 mg in capsules or tablets.

[0388] Example B15. Used as in any of Examples B8 to B14, wherein letrozole is administered orally in a dose of 2.5 mg.

[0389] Example B16. Use of a combination for manufacturing a drug that inhibits tumor growth or produces / increases tumor regression in patients with PIK3CA-mutated, hormone receptor-positive and HER2-negative locally advanced or metastatic breast cancer, the combination being a combination or use according to any one of Examples B1 to B15.

[0390] Example B17. The use as described in any of Examples B1 to B16, wherein the patient has locally advanced or metastatic breast cancer that is not treatable.

[0391] Example B18. Used as in any of Examples B1 to B17, wherein the patient experiences disease exacerbation during or within 12 months of completing adjunctive endocrine therapy with aromatase inhibitors or tamoxifen.

[0392] Example B19. Used as in any of Examples B1 to B18, wherein the patient has adequate hematological and organ function within 14 days prior to the start of the study treatment.

[0393] Example B20. Used as in any of Examples B1 to B19, wherein the patient is a postmenopausal patient.

[0394] Example B21. Use of a combination thereof for manufacturing a medicament for preventing or delaying the development of resistance to palbociclib-containing therapies in breast cancer, wherein the combination or use is according to any one of Examples B1 to B20.

[0395] Thanks to the teachings presented in the foregoing specification and related illustrations, those skilled in the art will recognize numerous modifications and other embodiments of the invention described herein. Therefore, it should be understood that the invention is not limited to the specific embodiments disclosed, and that modifications and other embodiments are intended to be included within the scope of the appended claims. Although specific terms are used herein, they are for general and descriptive purposes only and not for limiting purposes.

Claims

1. Use of a combination for the preparation of a medicine for treating patients with PIK3CA-mutated, hormone receptor-positive, and HER2-negative locally advanced or metastatic breast cancer, wherein the combination comprises: (i) inavolisib; (ii) palbociclib; and (iii) fulvestrant, wherein the combination is administered in a dosing regimen comprising: a. inavolisib administered via QD on days 1 to 28 of the first 28-day cycle; b. palbociclib administered via QD on days 1 to 21 of the first 28-day cycle; and c. fulvestrant administered on days 1 and 15 of the first 28-day cycle, wherein inavolisib is administered in the amount of 9 mg in an oral tablet, and palbociclib is administered in the amount of 125 mg in an oral capsule or tablet. The dose is 500 mg, and fulvestrant is administered via intramuscular (IM) infusion.

2. As claimed in claim 1, wherein the dosing regimen further comprises one or more additional 28-day cycles, comprising: a. administration of efliximab on days 1 to 28 of each additional 28-day cycle; b. administration of palbociclib on days 1 to 21 of each additional 28-day cycle; and c. administration of fulvestrant on day 1 of each additional 28-day cycle.

3. For the purposes of claim 1 or 2, wherein the patient has locally advanced or metastatic breast cancer that is not treatable.

4. For the purposes of request 1 or 2, wherein the patient’s disease worsens during adjuvant endocrine therapy or within 12 months after completing adjuvant endocrine therapy with aromatase inhibitors or tamoxifen.

5. As requested in item 1 or 2, wherein the patient has adequate hematological and organ function within 14 days prior to the start of the study treatment.

6. As requested in item 1 or 2, wherein the patient is a postmenopausal patient.

7. As requested in item 1 or 2, wherein the patient has estrogen receptor-positive breast cancer.

8. As requested in item 1 or 2, wherein the patient has a PIK3CA mutation containing one or more mutations selected from the group consisting of the following: E542K, E545K, Q546R, H1047L and H1047R.

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