An active substance that targets the asexual blood stage against malaria

Abstract

The invention relates to a compound that performs treatment by multi-protein inhibition method for use in the treatment of malaria. Said compound follows a different pathway from the pathway in which drug resistance occurs in malaria treatment and targets surface proteins named MSP1, PvDBP, RH5 and AMA1. By means of binding to these surface proteins with an affinity of -7.60, -8.10, -6.80 and -9.00 (kcal / mol), respectively, an alternative to drug resistance encountered in malaria treatment has been developed with 97% inhibition.

Description

[0001] AN ACTIVE SUBSTANCE THAT TARGETS THE ASEXUAL BLOOD STAGE AGAINST MALARIA

[0002] Technical Field

[0003] The invention relates to a compound targeting the asexual blood stage for use in the treatment of malaria. Said compound follows a different pathway than resistance mechanisms and prevents the disease from gaining resistance to this compound.

[0004] State of the Art

[0005] Malaria is a disease caused by 5 different Plasmodium parasites. Said parasite can be transmitted to humans through female mosquitoes. The disease, which can be transmitted from people with malaria to healthy people, is among the top 30 causes of death in the world, especially in developing countries. After the parasites that cause malaria enter the human blood, the parasites quickly settle in the liver cells. During this settlement, after asexual reproduction of all types of Plasmodium parasites, merozoites exit the liver and invade erythrsoids, initiating the symptomatic phase of malaria

[0001] . Malaria disease, which progresses in attacks, begins to show its symptoms approximately 1 -2 weeks after exposure to the parasite. In the majority of these attacks, patients experience tremors, high fever and loss of consciousness. Malaria disease causes liver damage and causes paralysis and death [2]. Microbial tests to detect the presence of Plasmodium parasites in blood samples taken from patients are used to diagnose people with malaria. Treatment of people with these parasites is of great importance in preventing the progression of the disease and saving the lives of patients. In current treatments, appropriate antimalarial methods are determined according to the type of Plasmodium parasite in the patient's blood and the patient's condition.

[0006] Today, antimalarial drugs containing the active ingredients chloroquine, quinine, doxycycline, atovaquone / proguanil, mefloquine and artemisinin are commonly used in the treatment of malaria. However, Plasmodium parasites have developed resistance to all of these antimalarial drugs [3], and the gradual increase in this resistance makes malaria a major threat. This causes the treatment to be interrupted and may even lead to treatment failure. As a result of this resistance, patients whose treatment is completed begin to show malaria attacks and other symptoms again within approximately three to four months following the end of treatment, although they continue their lives asymptomatically for a while [4]. In other words, mentioned antimalarial drugs have become insufficient in the treatment of malaria, and therefore new treatment methods and drugs are needed in the treatment of malaria.

[0007] All drugs that affect the current blood stage are used to prevent the detoxification of the heme compound, and all resistance mechanisms develop on this pathway. For this reason, an alternative to malaria treatment that acts through a pathway other than this pathway that causes resistance is required. However, there is a lack of effective compounds that can be used on this mechanistic pathway.

[0008] In the patent application numbered CN1 139427A in the state of the art, there are approaches aimed at treating malaria using malaria aspartic protease inhibitors. In this treatment method, inhibition is aimed by using 2,5-diol glutamine protease and its derivatives. However, said inhibition only inhibits the apartic protease. The inability to target more than one protein at the same time leads to limitations in treatment.

[0009] The utility model numbered US10183066B2 in the state of the art describes a vaccine used against Plasmodium parasites, especially Plasmodium falciparum, which causes malaria. This vaccine contains recombinant proteins and / or combinations of recombinant fusion proteins against the numerous surface proteins of the Plasmodium falciparum parasite. In addition, said vaccine contains antigens from the surface proteins of the pre-erythrocyte, blood and sexual stages of the parasite's life cycle. However, the vaccine described in this patent does not have therapeutic properties. This vaccine only protects people who have not been exposed to the Plasmodium falciparum parasite and has lower protection against other Plasmodium parasites that cause malaria. Therefore, the vaccine described in said patent document is insufficient to treat people with malaria.

[0010] Due to reasons such as the limitations and inadequacies of the solutions in the state of the art, the fact that the parasites that cause the disease become resistant to the drugs used in the treatment of malaria over time and the treatment is interrupted as a result of this resistance, drugs aiming to treat via enzyme inhibition pathways inhibit a single enzyme, the disease-blocking properties of the vaccines used vary depending on the type of parasite, and that they cannot be used in the treatment of people with malaria, it has become necessary to make a development in this field.

[0011] Brief Description and Aims of the Invention

[0012] The invention discloses an active substance that targets the asexual blood stage for use in the treatment of malaria. Said active substance is 1 ,1 -dioxo-2-(3-propylphenyl)- 4-[[3-[( 1 S)-1 -sulfanylethyl]phenyl]methyl]-1 A6,2,4-benzothiadiazin-3-on compound obtained by derivatisation of the structure named MMV008173 and is shown with Formula I.

[0013] An aim of the invention is to provide effective malaria treatment by following a different pathway from the pathway in which malaria-causing parasites acquire resistance to currently used drugs. In the invention, a compound that uses pathways to which malaria parasites are not resistant is used to be used in the treatment of malaria. As said active ingredient, 1 , 1 -dioxo-2-(3-propylphenyl)-4-[[3-[(1 S)-1 - sulfanylethyl]phenyl]methyl]-1A6,2,4-benzothiadiazin-3-on compound performs the treatment by providing competitive inhibition of 4 different merozoite surface proteins, which act on the invasion of erythrocytes by merozoites. This inhibition occurs through MSP1 , PvDBP, RH5 and AMA1 proteins during the attachment, deformation, apical end junction and mobile tight junction stages of erythrocyte invasion of merozoites, respectively. The invention aims to increase this inhibition percentage to higher values by derivatising the MMV008173 structure, which inhibits the parasites that cause malaria by binding to their surface proteins. Since the MMV008173 structure has a resistance mechanism, an effective treatment in malaria is aimed by interacting with the merozoite surface proteins of the MMV008173 derivative compound that is the subject of the invention and regulating the feature that causes the MMV008173 molecule to face resistance.

[0014] By means of this active ingredient, preveting drug resistance, which is frequently encountered in the treatment of malaria, and preventing the treatment of malaria from being interrupted by preventing the development of drug resistance are aimed. It is also possible to prevent disease recurrence caused by resistance. In the treatment that is the subject of the invention, in which resistance does not develop, an effective treatment is provided by inhibiting multiple proteins.

[0015] Description of Drawings

[0016] Figure 1 : The interaction maps of the molecule in the active site of the protein as a result of the docking study of the MSP1 - 1 ,1 -dioxo-2-(3-propylphenyl)-4-[[3-[(1 S)-1 - sulfanylethyl]phenyl]methyl]-1A6,2,4-benzothiadiazin-3-on molecule

[0017] Figure 2: The interaction maps of the molecule in the active site of the protein as a result of the docking study of the PvDBP- 1 ,1 -dioxo-2-(3-propylphenyl)-4-[[3-[(1 S)-1 - sulfanylethyl]phenyl]methyl]-1A6,2,4-benzothiadiazin-3-on molecule

[0018] Figure 3: The interaction maps of the molecule in the active site of the protein as a result of the docking study of the RH5-1 - 1 -dioxo-2-(3-propylphenyl)-4-[[3-[(1 S)-1 - sulfanylethyl]phenyl]methyl]-1A6,2,4-benzothiadiazin-3-on molecule

[0019] Figure 4: The interaction maps of the molecule in the active site of the protein as a result of the docking study of the AMA1 -1 - 1 -dioxo-2-(3-propylphenyl)-4-[[3-[(1 S)-1 - sulfanylethyl]phenyl]methyl]-1A6,2,4-benzothiadiazin-3-on molecule Detailed Description of the Invention

[0020] The invention relates to an active ingredient to be used in the treatment of malaria by inhibiting multiple proteins. Said active substance represented by formula I is 1 ,1 - dioxo-2-(3-propylphenyl)-4-[[3-[(1 S)-1 -sulfanylethyl]phenyl]methyl]-1A6,2,4- benzothiadiazin-3-on.

[0021] The compound of the invention targets 4 different merozoite surface proteins named MSP1 , PvDBP, RH5 and AMA1 and provides treatment of the disease by inhibiting these proteins. Said proteins named MSP1 (Merozoite Surface Protein 1 ), PvDBP (Plasmodium vivax Duffy Binding Protein), RH5 (Reticulocyte binding protein Homolog 5) and AMA1 (Apical Membrane Antigen 1 ) are found on the surface of Plasmodium parasites that cause malaria. After malaria enters the human body and proliferates asexually in the liver, merozoites exit the liver and invade erythrocytes. As a result of this invasion, symptoms occur in a person exposed to one of the Plasmodium parasites. The compound, which targets 4 different merozoite surface proteins named MSP1 , PvDBP, RH5 and AMA1 , found on the surface of parasites during this asexual reproduction, binds to these surface proteins with high affinity. The interaction maps obtained as a result of the docking study are determined (Figure 1 -4).

[0022] In the invention, MMV008173, one of the compounds examined in the Malaria Box set, showed 97% inhibition in the 3D7 wild type strain, more than the approximately 70- 80% inhibition expected from an invasion inhibitor, and also showed 76% inhibition with a 21 % decrease in the DD2 resistant strain. Considering these results and gradual inhibition tests [5], it is understood that the compound MMV008173 shown by Formula II acts inside the cell due to the decrease in inhibition in the DD2 strain, although there is no resistance mechanism. The MMV008173 molecule acts within the cell and attaches to the existing resistance mechanism. When the studies in the state of the art [6,7] are examined for comparison, it is shown that the MMV020291 invasion inhibitor has no effect after invasion and does not interfere with resistance mechanisms. MMV008173 ligand binds with MSP1 , DBP, RH5 and AMA1 proteins, showing 76% inhibition (DD2 strain), and then, the inhibited MSP1 protein, which is incorporated into the structure of the food vacuole membrane formed through endocytosis, cannot act within the cell and increases the inhibition rate to 97% (3D7 strain). In the resistant strain, the compound MMV008173 bound to the MSP1 protein is disconnected and thrown out of the cell, and MSP1 cannot inhibit it. By correcting this problem encountered in the resistant strain as a result of the derivatisation, 1 ,1 -dioxo-2-(3- propylphenyl)-4-[[3-[(1 S)-1 -sulfanylethyl]phenyl]methyl]-1 A6,2,4-benzothiadiazin-3-on is obtained and this compound does not interfere with the resistance mechanism, and the connections made by the MMV008173 compound with proteins are strengthened.

[0023] Formula II REFERENCES

[0024] [1] Budan Qah§kan B, Somer A “Sitma (Malarya) ve Tedavisi”. Klinik Tip Pediatri Dergisi, Cilt:10, Sayi:6. Kasim-Arahk 2018

[0025] [2] Caraballo H, King K "Emergency department management of mosquito-borne illness: malaria, dengue, and West Nile virus". Emergency Medicine Practice. (May 2014). 16 (5): 1-23, quiz 23-4. PMID 25207355. S2CID 23716674. Archived from the original on 2016-08-01 .

[0026] [3] Dikici N, “Sitma Tedavisi” Turkiye Klinikleri J Inf Dis-Special Topics. 2012;5(2):30-

[0027] 44

[0028] [4] Qokga F, Battal I, Altay G. “Bir Plasmodium Vivax Malaryasi: Primakin

[0029] Direngliligi?” (1995). Mikrobiyol Bult, 29:296-298

[0030] [5] Van Voorhis WC, Adams JH, Adelfio R, Ahyong V, Akabas MH, et al. (2016)

[0031] Open Source Drug Discovery with the Malaria Box Compound Collection for Neglected Diseases and Beyond. PLOS Pathogens 12(7): e1005763.

[0032] [6] William Nguyen, Madeline G. Dans, Anna Ngo, Maria R. Gancheva, Ornella

[0033] Romeo, Sandra Duffy, Tania F. de Koning-Ward, Kym N. Lowes, Helene Jousset Sabroux, Vicky M. Avery, Danny W. Wilson, Paul R. Gilson, Brad E. Sleebs.Structure activity refinement of phenylsulfonyl piperazines as antimalarials that block erythrocytic invasion. European Journal of Medicinal Chemistry, Volume 214.2021 ,113253, ISSN 0223- 5234, https: / / doi.Org / 10.1016 / j.ejmech.2O21 .113253.

[0034] [7] Dans MG, Weiss GE, Wilson DW, Sleebs BE, Crabb BS, de Koning-Ward TF,

[0035] Gilson PR. Screening the Medicines for Malaria Venture Pathogen Box for invasion and egress inhibitors of the blood stage of Plasmodium falciparum reveals several inhibitory compounds. Int J Parasitol. 2020 Mar;50(3):235-252.

Claims

CLAIMS1. A malaria drug candidate molecule with the skeleton of the molecule 1 ,1 -dioxo¬2-(3-propylphenyl)-4-[[3-[(1 S)-1 -sulfanylethyl]phenyl]methyl]-1 A6,2,4- benzothiadiazin-3-on (Formula I) below.Formula I2. A compound according to claim 1 for use in the treatment of malaria, which functions in erythrocyte invasion.

3. A compound according to claim 1 , wherein it is used in the treatment of malaria by means of the competitive inhibition of MSP1 , PvDBP, RH5 and AMA1 surface proteins.

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