Parasitic Amebiasis

We secured a license with the Unites States National Institutes of Health (NIH) to address this problem. The technology which is in development consists of targeting Giardia Lamblia with Auranofin, a drug that is already approved for other uses, such as rheumatoid arthritis. By choosing this drug, we know the drug is considered safe for human consumption, we are encouraged by the other applications for this drug that are currently being tested, E Histolytica, Cryptosporidium, other parasites that cause many deaths due to amebic dysentery or amebiasis.
When we negotiated the contract we specifically requested that our NIH license for the technology be provided free to low-income countries and we duly signed it. In light of the many other possible applications of this drug, if it gains approval, we would like to reduce the cost of this potentially life-saving drug. We intend to contract manufacture it and supply it cheaply to everyone who needs it. After high-throughput testing of 4096 compounds, Auranofin was revealed to researcher Wei Zheng as one of 43 promising compounds for treating Giadiasis. Metranidazole is the current drug of choice, however, breakthrough resistance is occurring as this is a widely used antibiotic. As we look for alternatives this could be a candidate.

The NIH has decided to fund a Phase II trial under the direction of Dr. Sharon Reed in Bangladesh at the International Diarrheal center. This emphasizes that the potential for this drug is recognized by the NIH.

Dr. Sujata Baveja, Microbiology Professor Lokmany Tilak Hospital Sion Mumbai is currently screening for Giardia in the Dharavi slum (featured in the movie “ Slum Dog Millionaire”). Subrimed is sponsoring the testing and screening.

-Social Pharma Army

Dr . Sharon Reed,Professor UC San Diego Medical School

will start Phase II study with Auranofin in July 2015

• Director of the Clinical Microbiology Laboratory | M.D. – Harvard University | Residency Training: Peter Bent Brigham Hospital Boston, Massachusetts | Clinical Specialty: Comparative Physiology

“From a collaborative high through put screen of thousands of compounds, we identified an FDA-approved drug, auranofin, which is an oral gold-containing compound that has efficacy against all anaerobic protozoa, Entamoeba, Giardia, and Trichomonas, even those resistant to metronidazole. We are planning a clinical trial of auranofin against E. histolytica and Giardia with collaborators at the International Centre for Research in Diarrhoeal Disease Research, Bangladesh. Toxoplasmosis is one of the most common parasitic infections of man. The majority of patients have asymptomatic, dormant infection for life, however serious complications result from congenital infection or reactivation disease in immunocompromised patients, particularly those with AIDS. This project will focus on the role of cysteine proteinases in the pathogenesis of toxoplasmosis. We have cloned and characterized the three major classes of cathepsins, a cathepsin B, L, and three cathepsin Cs and are looking at inhibitors, which target these enzymes. In addition, auranofin also targets the thiol reductase system in T. gondii and may prove to be a new therapeutic agent for toxoplasmosis as well”.

We are excited about the technology:

Antimicrob Agents Chemother. 2013 May;57(5):2029-35. doi: 10.1128/AAC.01675-12. Epub 2013 Feb 12.A reprofiled drug, auranofin, is effective against metronidazole-resistant Giardia lamblia.Tejman-Yarden N1, Miyamoto Y, Leitsch D, Santini J, Debnath A, Gut J, McKerrow JH, Reed SL, Eckmann L.

• 1Department of Medicine, University of California, San Diego, La Jolla, California, USA.

Giardiasis is one of the most common causes of diarrheal disease worldwide. Treatment is primarily with 5-nitro antimicrobials, particularly metronidazole. Resistance to metronidazole has been described, and treatment failures can occur in up to 20% of cases, making development of alternative antigiardials an important goal. To this end, we have screened a chemical library of 746 approved human drugs and 164 additional bioactive compounds for activity against Giardia lamblia. We identified 56 compounds that caused significant inhibition of G. lamblia growth and attachment. Of these, 15 were previously reported to have antigiardial activity, 20 were bioactive but not approved for human use, and 21 were drugs approved for human use for other indications. One notable compound of the last group was the antirheumatic drug auranofin. Further testing revealed that auranofin was active in the low (4 to 6)-micromolar range against a range of divergent G. lamblia isolates representing both human-pathogenic assemblages A and B. Most importantly, auranofin was active against multiple metronidazole-resistant strains. Mechanistically, auranofin blocked the activity of giardial thioredoxin oxidoreductase, a critical enzyme involved in maintaining normal protein function and combating oxidative damage, suggesting that this inhibition contributes to the antigiardial activity. Furthermore, auranofin was efficacious in vivo, as it eradicated infection with different G. lamblia isolates in different rodent models. These results indicate that the approved human drug auranofin could be developed as a novel agent in the armamentarium of antigiardial drugs, particularly against metronidazole-resistant strains.

We are excited about the technology (cont.)

PLoS Negl Trop Dis. 2014 Jul 31;8(7):e2973. doi: 10.1371/journal.pntd.0002973. eCollection 2014.Auranofin is highly efficacious against Toxoplasma gondii in vitro and in an in vivo experimental model of acute toxoplasmosis.Andrade RM1, Chaparro JD2, Capparelli E2, Reed SL3.

• 1Department of Medicine, University of California, San Diego, San Diego, California, United States of America. | 2Department of Pediatrics, University of California, San Diego, San Diego, California, United States of America. | 3Department of Medicine, University of California, San Diego, San Diego, California, United States of America; Department of Pathology, University of California, San Diego, San Diego, California, United States of America.

BACKGROUND:
The mainstay of toxoplasmosis treatment targets the folate biosynthetic pathways and has not changed for the last 50 years. The activity of these chemotherapeutic agents is restricted to one lifecycle stage of Toxoplasma gondii, they have significant toxicity, and the impending threat of emerging resistance to these agents makes the discovery of new therapies a priority. We now demonstrate that auranofin, an orally administered gold containing compound that was FDA approved for treatment of rheumatoid arthritis, has activity against Toxoplasma gondii in vitro (IC50 = 0.28 µM) and in vivo (1 mg/kg).
METHODS/PRINCIPAL FINDINGS:
Replication within human foreskin fibroblasts of RH tachyzoites was inhibited by auranofin. At 0.4 µM, auranofin inhibited replication, as measured by percent infected fibroblasts at 24 hrs, (10.94% vs. 24.66% of controls; p = 0.0003) with no effect on parasite invasion (16.95% vs. 12.91% p = 0.4331). After 18 hrs, 62% of extracellular parasites treated with auranofin were non-viable compared to control using an ATP viability assay (p = 0.0003). In vivo, a previously standardized chicken embryo model of acute toxoplasmosis was used.

Fourteen day old chicken embryos were injected through the chorioallantoic vein with 1×104 tachyzoites of the virulent RH strain. The treatment group received one dose of auranofin at the time of inoculation (1 mg/kg estimated body weight). On day 5, auranofin-treated chicken embryos were 100% protected against death (p = 0.0002) and had a significantly reduced parasite load as determined by histopathology, immunohistochemistry and by the number of parasites quantified by real-time PCR.
CONCLUSIONS:
These results reveal in vitro and in vivo activity of auranofin against T. gondii, suggesting that it may be an effective alternative treatment for toxoplasmosis.

Gut Microbes. 2013 Jan-Feb;4(1):66-71. doi: 10.4161/gmic.22596. Epub 2012 Nov 8.Reprofiled drug targets ancient protozoans: drug discovery for parasitic diarrheal diseases.Debnath A1, Ndao M, Reed SL.

• 1Center for Discovery and Innovation in Parasitic Diseases, University of California, San Francisco, San Francisco, CA, USA.anjan.debnath@ucsf.edu

Recently, we developed a novel automated, high throughput screening (HTS) methodology for the anaerobic intestinal parasite Entamoeba histolytica. We validated this HTS platform by screening a chemical library containing US Food and Drug Administration (FDA)-approved drugs and bioactive compounds. We identified an FDA-approved drug, auranofin, as most active against E. histolytica both in vitro and in vivo. Our cell culture and animal studies indicated that thioredoxin reductase, an enzyme involved in reactive oxygen species detoxification, was the target for auranofin in E. histolytica. Here, we discuss the rationale for drug development for three parasites which are major causes of diarrhea worldwide, E. histolytica, Giardia lamblia and Cryptosporidium parvum and extend our current finding of antiparasitic activity of auranofin to Entamoeba cysts, G. lamblia and C. parvum. These studies support the use of HTS assays and reprofiling FDA-approved drugs for new therapy for neglected tropical diseases.
KEYWORDS:
Cryptosporidium parvum; Entamoeba; Giardia; auranofin; diarrheal diseases; drug discovery; high throughput screen; orphan drug; protozoan parasites; thioredoxin reductase

We would like to raise $30,000. 100% will be used for license/patent expenses, attorney fees and testing/trials, not a penny will go to subrimed staffing costs or administration. If we raise more we would like to put 100% towards any further testing/ clinical trial costs and contract manufacture.