Use of pentagastrin in the preparation of a medicament for the treatment of immune checkpoint inhibitor associated colitis

Abstract

This invention discloses the application of gastric pentadecapeptide in the preparation of drugs for treating immune checkpoint inhibitor-induced colitis, belonging to the field of biomedical technology. This is the first time gastric pentadecapeptide has been applied to the treatment of immune checkpoint inhibitor-induced colitis. Experiments show that gastric pentadecapeptide can effectively alleviate colitis induced by CTLA-4 antibody and the combined use of CTLA-4 and PD-1 antibody, manifested by weight recovery, improved colon length, repair of crypt structure, and reduction of inflammatory area; simultaneously, it downregulates the expression of pro-inflammatory factors TNF-α, IL-6, and IL-1β, and upregulates the expression of anti-inflammatory factor TGF-β. More importantly, gastric pentadecapeptide exerts its intestinal protective effect without weakening the anti-tumor efficacy of immune checkpoint inhibitors. This invention also provides a pharmaceutical composition containing gastric pentadecapeptide and immune checkpoint inhibitors, as well as a gastric pentadecapeptide enema. This invention solves the problem that existing drugs may weaken anti-tumor efficacy due to non-specific immunosuppression, achieving a clinical breakthrough of "balancing efficacy and toxicity."

Description

Technical Field

[0001] This invention belongs to the field of biomedical technology, specifically relating to the application of gastric pentadecapeptide in the preparation of drugs for treating immune checkpoint inhibitor-associated colitis. Background Technology

[0002] Colitis is a digestive system disease characterized by intestinal inflammation, mucosal damage, and destruction of crypt structures. Its pathogenesis involves multiple factors, including immune dysregulation, intestinal barrier dysfunction, and regenerative disorders. Among these, intestinal immune dysfunction is the core mechanism driving the development of colitis, manifested as the upregulation of pro-inflammatory factors (such as TNF-α, IL-6, and IL-1β) and the downregulation of anti-inflammatory factors (such as TGF-β). In the aforementioned subtypes of colitis, immune checkpoint inhibitor-induced immune colitis is one of the most serious and common complications in the field of tumor immunotherapy.

[0003] Tumor immune checkpoint inhibitor therapy (IUI) involves using antibodies (such as CTLA-4 antibodies and PD-1 / PD-L1 antibodies) to block the binding of immune checkpoints to their ligands, thereby relieving immune checkpoint-mediated immunosuppression, promoting T-cell activation, and enhancing the anti-tumor immune response. Currently, IUI has achieved breakthrough progress in the treatment of various malignant tumors. However, because these drugs work by enhancing the host immune response and pro-inflammatory activity, they can induce inflammation-related adverse reactions, leading to damage to multiple organs, such as immune-mediated colitis. Currently, clinical treatment of IUI induced colitis mainly relies on glucocorticoids or immunosuppressants. However, these drugs are mostly symptomatic treatments, aiming to control the inflammatory response and alleviate clinical symptoms, but they suffer from problems such as unsatisfactory efficacy, significant side effects, and high relapse rates. Long-term use can lead to serious adverse reactions such as immunosuppression, increased risk of infection, osteoporosis, and metabolic disorders. Therefore, finding intervention strategies that can prevent or mitigate IUI without affecting anti-tumor efficacy has become an urgent need in the field of tumor immunotherapy.

[0004] BPC-157 (also known as Body Protection Compound-157) is an endogenous polypeptide derivative composed of 15 amino acids. Previous studies have reported that BPC-157 promotes the healing of various tissue injuries, demonstrating good repair effects in animal models of skin burns, gastric ulcers, fracture healing, and nerve injury. However, current research mainly focuses on stress-related diseases and traditional chemically induced or ischemic inflammation models. No reports have been found regarding the therapeutic effects of BPC-157 on immune colitis, a novel and complex subtype of colitis induced by immune checkpoint inhibitors, or its potential for combination therapy with immune checkpoint inhibitors. In particular, the regulatory effects of BPC-157 on the intestinal immune microenvironment, its potential impact on T cell activity, and its interaction mechanisms with CTLA-4 and PD-1 / PD-L1 antibodies remain unknown. How to retain the anti-tumor efficacy of immune checkpoint inhibitors while reducing their intestinal toxicity is one of the core challenges in the field of tumor immunotherapy. Summary of the Invention

[0005] Existing anti-inflammatory drugs exert their effects through non-specific immunosuppression, which not only increases the risk of infection and causes systemic side effects such as metabolic disorders, but may also weaken the anti-tumor immune response, leading to decreased patient survival benefits. There is a lack of technical strategies to effectively prevent or mitigate immune checkpoint inhibitor-induced immune colitis without affecting its anti-tumor efficacy. The purpose of this invention is to provide the application of gastric pentadecapeptide in the preparation of drugs for treating immune checkpoint inhibitor-related colitis, thereby addressing the lack of existing treatment methods that balance intestinal protection and anti-tumor efficacy. This invention is the first to demonstrate that gastric pentadecapeptide can significantly reduce intestinal damage while retaining anti-tumor efficacy, providing a novel combination therapy for clinical use and filling a gap in this technical field.

[0006] To achieve the above objectives, the present invention employs the following technical solution: This invention provides the use of gastric pentadecapeptide or a pharmaceutically acceptable salt thereof in the preparation of a medicament for treating immune checkpoint inhibitor-induced colitis.

[0007] The immune checkpoint inhibitors mentioned are one or more of CTLA-4 inhibitors, PD-1 inhibitors, or PD-L1 inhibitors. They cover the mainstream immune checkpoint inhibitor types on the market, including the CTLA-4 antibody ipilimumab, the PD-1 antibody pembrolizumab / nivolumab, and the PD-L1 antibody atezolizumab, etc., and have a wide range of applications.

[0008] The use of gastric pentadecapeptide or a pharmaceutically acceptable salt thereof in the preparation of medicaments for use in combination with immune checkpoint inhibitors, wherein the medicaments are intended to alleviate or prevent colitis induced by the immune checkpoint inhibitors without affecting the antitumor efficacy of the immune checkpoint inhibitors. This addresses the core challenge of existing anti-inflammatory drugs potentially weakening their antitumor immune effects due to nonspecific immunosuppression, achieving a clinical breakthrough that balances efficacy and toxicity, and providing an important adjuvant therapy strategy for the continued clinical application of immune checkpoint inhibitors.

[0009] This invention provides the use of gastric pentadecapeptide or a pharmaceutically acceptable salt thereof in the preparation of enemas for the treatment of immune-mediated colitis. By preparing gastric pentadecapeptide into an enema, the drug can act directly on the intestinal lesions, increasing local drug concentration and enhancing therapeutic efficacy, while reducing systemic exposure and potential systemic side effects. This is particularly suitable for patients with immune-mediated colitis whose lesions are confined to the colon, thus enriching clinical dosing options.

[0010] This invention provides a pharmaceutical composition for treating colitis, comprising: (a) A therapeutically effective amount of gastric pentadecapeptide or a pharmaceutically acceptable salt thereof; and (b) An immune checkpoint inhibitor, wherein the immune checkpoint inhibitor is selected from CTLA-4 antibody, PD-1 antibody or a combination thereof; The pharmaceutical composition is used to alleviate or prevent colitis induced by the immune checkpoint inhibitor without affecting the antitumor efficacy of the immune checkpoint inhibitor.

[0011] The immune checkpoint inhibitors are CTLA-4 antibodies and / or PD-1 antibodies. In dual immunotherapy using CTLA-4 and PD-1 antibodies, this composition can enhance the anti-tumor immune response while effectively inhibiting severe colitis, addressing the key issue of dose-limiting toxicities in dual immunotherapy and potentially expanding the beneficiary population.

[0012] The use of gastric pentadecapeptide or a pharmaceutically acceptable salt thereof in the preparation of drugs for repairing colonic mucosal damage, restoring crypt structure, downregulating the expression of pro-inflammatory factors TNF-α, IL-6, and IL-1β, and upregulating the expression of anti-inflammatory factor TGF-β.

[0013] The colitis referred to is ulcerative colitis or immune checkpoint inhibitor-induced immune colitis.

[0014] The use of gastric pentadecapeptide or a pharmaceutically acceptable salt thereof in the preparation of a medicament for treating colitis, said medicament for reducing colonic shortening, alleviating weight loss, reducing the inflammatory area of ​​colonic tissue, and reducing inflammatory cell infiltration.

[0015] Compared with the prior art, the present invention has the following beneficial effects: The application of gastric pentadecapeptide or its pharmaceutically acceptable salt in the preparation of a drug for treating immune-related intestinal injury provided by this invention is the first time that the application of gastric pentadecapeptide and its pharmaceutically acceptable salt has been precisely limited to the specific disease subtype of "immune checkpoint inhibitor-induced colitis". This expands its application from the traditional field of wound healing to the emerging and clinically urgent field of complications related to tumor immunotherapy, providing a new and effective intervention for immune checkpoint inhibitor-induced colitis.

[0016] Furthermore, animal experiments confirmed that gastric pentadecapeptide significantly alleviated immune checkpoint inhibitor-induced colitis (manifested as weight recovery, improved colon length, repair of crypt structures, and reduction of inflammatory area) without weakening the anti-tumor efficacy of immune checkpoint inhibitors (no significant difference in tumor volume and weight between the combination therapy group and the immune checkpoint inhibitor monotherapy group). This solves the core problem that existing anti-inflammatory drugs may weaken the anti-tumor immune effect due to non-specific immunosuppression, providing an important adjuvant therapy strategy for the continued clinical application of immune checkpoint inhibitors. It covers the current mainstream types of immune checkpoint inhibitors in clinical practice (CTLA-4 inhibitors, PD-1 inhibitors, PD-L1 inhibitors) and verified that gastric pentadecapeptide has significant therapeutic effects on colitis induced by CTLA-4 inhibitor monotherapy and CTLA-4+PD-1 inhibitor combination therapy. Especially in the high-risk scenario of dual immunotherapy (CTLA-4+PD-1), gastric pentadecapeptide can still effectively protect the intestine, showing broad clinical applicability and higher clinical value. A local administration regimen of gastric pentadecapeptide as an enema can directly act on the lesion site in the colon, reducing systemic side effects.

[0017] The pharmaceutical composition provided by this invention integrates two active ingredients into the same formulation, providing a "ready-to-use" combination therapy for clinical use. This simplifies the administration process, improves patient compliance, and ensures that the two work synergistically in vivo. While exerting the anti-tumor effect of immune checkpoint inhibitors, the gastric pentadecapeptide actively prevents or alleviates colitis, achieving an integrated therapeutic goal. Attached Figure Description

[0018] Figure 1 The figure shows the effect of gastric pentadecapeptide on body weight changes in CTLA-4 antibody-induced PD-1 gene knockout mice with immune colitis. Figure 2 The figure shows the effect of gastric pentadecapeptide on colon length in CTLA-4 antibody-induced PD1 knockout mice with immune colitis. Figure 3This is a staining image of colon tissue from PD1 gene knockout mice with immune colitis induced by CTLA-4 antibody-induced gastric pentadecapeptide. Figure 4 The statistical analysis of the inflammatory area of ​​colon tissue after staining in PD1 gene knockout mice with immune colitis induced by gastric pentadecapeptide-CTLA-4 antibody. Figure 5 Figure showing the protective effect of gastric pentadecapeptide against immune checkpoint inhibitor-induced colitis and its influence on tumor growth in a PD1 gene knockout tumor-bearing mouse model. Detailed Implementation

[0019] To enable those skilled in the art to better understand the present invention, the technical solution of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0020] The gastric pentadecapeptide used in this embodiment of the invention was prepared according to the standard solid-phase polypeptide synthesis method and purified by high performance liquid chromatography with a purity ≥98%.

[0021] The present invention will now be described in further detail: Example 1: Protective effect of gastric pentadecapeptide on immune colitis induced by CTLA-4 antibody in PD-1 gene knockout mice.

[0022] Male C57BL / 6 PD-1 knockout mice aged 6-8 weeks (purchased from Air Force Medical University) were randomly divided into 6 groups, with 5 mice in each group. The control group received intramuscular injections of saline every 3 days; the low-dose gastric pentadecapeptide group received intramuscular injections of 5 μg / kg gastric pentadecapeptide daily; the high-dose gastric pentadecapeptide group received intramuscular injections of 10 μg / kg gastric pentadecapeptide daily; the CTLA-4 group received intramuscular injections of CTLA-4 antibody (purchased from Selleck Chemicals, catalog number A2103, clone number 9H10, 10 mg / kg) every 3 days for 42 consecutive days; the CTLA-4 + low-dose gastric pentadecapeptide group received intramuscular injections of CTLA-4 antibody every 3 days, along with intramuscular injections of 5 μg / kg gastric pentadecapeptide daily; and the CTLA-4 + high-dose gastric pentadecapeptide group received intramuscular injections of CTLA-4 antibody every 3 days, along with intramuscular injections of 10 μg / kg gastric pentadecapeptide daily.

[0023] Mice were weighed every two days during the experiment. On day 42, mice were sacrificed, and colon tissue was collected to measure its length. Specific results can be found in [link to relevant documentation]. Figures 1-2 As shown.

[0024] In addition, male C57BL / 6PD-1 gene knockout mice aged 6-8 weeks were randomly divided into 6 groups, with 10 mice in each group. The grouping information was the same as in the previous experiment. Mice were sacrificed on day 42 of the experiment, and colon tissue was collected for H&E staining to observe pathological changes. Specific results can be found in [link to relevant documentation]. Figures 3-4 As shown.

[0025] From the appendix Figure 1 The data show that the weight gain of mice in the normal control group was steady; the weight gain of mice in the CTLA-4 group slowed down from week 3, and the weight began to decrease after week 5, with a decrease of about 8% by the end of week 6; the weight loss trend of mice in the CTLA-4 + gastric pentadecapeptide low-dose group was similar to that of the CTLA-4 group, with no significant difference; the weight gain of mice in the CTLA-4 + gastric pentadecapeptide high-dose group was steady, with no significant difference from the normal control group, but a significant difference compared with the CTLA-4 group.

[0026] From the appendix Figure 2 The data show that the colon length in the normal control group was 8.1 cm; the colon length in the CTLA-4 group was significantly shortened to 6.2 cm; the colon length in the low-dose CTLA-4 + gastric pentadecapeptide group was 7.1 cm, which was significantly different from that in the CTLA-4 group; and the colon length in the high-dose CTLA-4 + gastric pentadecapeptide group was significantly increased compared with that in the CTLA-4 group, approaching the level of the normal control group.

[0027] Depend on Figure 3 and Figure 4 Data shows that H&E staining of colon tissue revealed that the colon structure was normal in the normal control group; shortened villi, crypt damage, and inflammatory cell infiltration were observed in the CTLA-4 group; tissue damage was slightly improved in the low-dose CTLA-4 + gastric pentadecapeptide group; and the colon tissue structure of the high-dose CTLA-4 + gastric pentadecapeptide group was basically restored to normal, with intact villi, clear crypts, and significantly reduced inflammatory cell infiltration.

[0028] The above data indicate that gastric pentadecapeptide can effectively alleviate immune colitis induced by CTLA-4 antibody in PD-1 gene knockout mice, and the effect is significant at high doses (10 μg / kg).

[0029] Example 2: Therapeutic effect of gastric pentadecapeptide on immune checkpoint inhibitor-induced colitis in a PD-1 gene knockout tumor model Establishment of a subcutaneous xenograft mouse model: Melanoma cells (1×10⁻⁶) were subcutaneously injected into the right back of 6-8 week old male PD-1 gene knockout C57BL / 6 mice. 6 (One per tumor). When the tumor volume reaches approximately 75mm... 3Mice bearing tumors were randomly divided into four groups of five each. The control group received intramuscular injections of saline every three days; the gastric pentadecapeptide group received intramuscular injections of 10 μg / kg gastric pentadecapeptide daily; the CTLA-4 group received intramuscular injections of CTLA-4 antibody (purchased from Selleck Chemicals, models A2103 and A2122, clone numbers 9H10 and RMP1-14, 10 mg / kg) every three days; and the CTLA-4 + gastric pentadecapeptide group received intramuscular injections of CTLA-4 antibody and PD-1 antibody every three days, along with daily intramuscular injections of 10 μg / kg gastric pentadecapeptide. Mice were sacrificed on day 42, and colon tissue was collected for pathological examination. Tumor tissue was also weighed.

[0030] Tumor growth curves and tumor weight results show ( Figure 5 The tumor volume and weight in the CTLA-4 group were significantly smaller than those in the control group (p<0.01), indicating that the CTLA-4 antibody has a significant anti-tumor effect. The tumor volume and weight in the CTLA-4 + gastric pentadecapeptide group were not significantly different from those in the CTLA-4 group, indicating that gastric pentadecapeptide can alleviate colitis induced by immune checkpoint inhibitors without affecting the anti-tumor efficacy.

[0031] The experiments in this embodiment demonstrate that gastric pentadecapeptide has good safety and can be used in combination with immune checkpoint inhibitors without affecting the anti-tumor efficacy, thus alleviating colitis induced by these inhibitors. This discovery provides a new solution to the clinical challenge of balancing efficacy and toxicity in tumor immunotherapy.

[0032] In summary, this invention systematically verified the therapeutic effect of gastric pentadecapeptide on colitis using various animal models of colitis, and preliminarily revealed its molecular mechanism of promoting intestinal repair by regulating crosstalk between immune cells and intestinal stem cells. As an endogenous polypeptide derivative, gastric pentadecapeptide exhibits good safety and application prospects, providing a new strategy and drug option for the treatment of colitis.

[0033] The above content is only for illustrating the technical concept of the present invention and should not be construed as limiting the scope of protection of the present invention. Any modifications made to the technical solution based on the technical concept proposed in this invention shall fall within the scope of protection of the claims of this invention.

Claims

1. The use of gastopentide or a pharmaceutically acceptable salt thereof in the preparation of a medicament for the treatment of immune checkpoint inhibitor-induced colitis.

2. The application according to claim 1, characterized in that, The immune checkpoint inhibitor is one or more of CTLA-4 inhibitors, PD-1 inhibitors, or PD-L1 inhibitors.

3. The use of gastric pentadecapeptide or a pharmaceutically acceptable salt thereof in the preparation of a medicament for use in combination with an immune checkpoint inhibitor, characterized in that, The drug, with gastopentapeptide or a pharmaceutically acceptable salt thereof as its active ingredient, is used to alleviate or prevent colitis induced by the immune checkpoint inhibitor without affecting the antitumor efficacy of the immune checkpoint inhibitor.

4. The application according to claim 3, characterized in that, The immune checkpoint inhibitor is one or more of CTLA-4 inhibitors, PD-1 inhibitors, or PD-L1 inhibitors.

5. The use of gastric pentadecapeptide or a pharmaceutically acceptable salt thereof in the preparation of enemas for the treatment of immune colitis.

6. A pharmaceutical composition for treating colitis, characterized in that, Include: (a) A therapeutically effective amount of gastric pentadecapeptide or a pharmaceutically acceptable salt thereof; and (b) An immune checkpoint inhibitor, wherein the immune checkpoint inhibitor is selected from CTLA-4 antibody, PD-1 antibody or a combination thereof; The pharmaceutical composition is used to alleviate or prevent colitis induced by the immune checkpoint inhibitor without affecting the antitumor efficacy of the immune checkpoint inhibitor.

7. The pharmaceutical composition according to claim 6, characterized in that, The immune checkpoint inhibitor is a CTLA-4 antibody or a combination of a PD-1 antibody.

8. The use of gastric pentadecapeptide or a pharmaceutically acceptable salt thereof in the preparation of drugs for repairing colonic mucosal damage, restoring crypt structure, downregulating the expression of pro-inflammatory factors TNF-α, IL-6, and IL-1β, and upregulating the expression of anti-inflammatory factor TGF-β.

9. The application according to claim 8, characterized in that, The colitis mentioned is immune colitis induced by immune checkpoint inhibitors.

10. The use of gastric pentadecapeptide or a pharmaceutically acceptable salt thereof in the preparation of a medicament for treating colitis, characterized in that, The drug is used to reduce colon shortening, alleviate weight loss, reduce the inflammatory area of ​​colon tissue, and reduce inflammatory cell infiltration.

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