The drug development process can be incredibly costly, both in terms of the financial commitment required and the time necessary to advance a drug to approval and production.
Drug repurposing offers an alternative path to drug development by leveraging previous research.
The drug development process can be incredibly costly, both in terms of the financial commitment required and the time necessary to advance a drug to approval and production. When setting on a path towards the production of a new drug, companies face a lengthy drug discovery and clinical process involving initial research, drug synthesis, toxicity and efficacy, API prep and formulation studies, all of which come before the clinical trial process itself. The early stages of the drug development process can also be the most financially costly, with companies committing hundreds of millions of dollars towards a drug with no guarantee that it will make it to the marketplace. In order to cut down the drug development timeline and leverage the research and development work of past companies, a number of upcoming pharmaceutical companies are working to repurpose or reposition established drugs to shorten the path to production.
Drug development and repurposing
Drug repurposing involves the targeted development of a drug that has previously passed safety testing for human use. By repurposing a drug rather than developing a new compound, companies are able to leverage the work done by previous developers in order to discover new medicines or products with novel applications. According to the National Center for Advancing Translational Sciences, drug repurposing is a strategy that can effectively reduce the time frame for drug development while also reducing costs and improving success rates.
“Developing a brand-new drug takes an enormous amount of time, money and effort, mainly due to bottlenecks in the therapeutic development process. Delays and barriers mean that translation of a promising molecule into an approved drug often takes more than 14 years. Drug repurposing is one such strategy,” said the NCATS on its website. “Many agents approved for other uses already have been tested in humans, so detailed information is available on their pharmacology, formulation and potential toxicity. Because repurposing builds upon previous research and development efforts, new candidate therapies could be ready for clinical trials quickly, speeding their review by the Food and Drug Administration.”
Drug repurposing versus repositioning
Like drug repurposing, drug re-positioning also aims to leverage drugs that have advanced to the clinical trial stage of development but have failed or stalled at that stage. Each phase of a clinical drug study has its own purpose and goals, creating a number of hurdles for drug development companies to overcome as they work to prove the safety and efficacy of the proposed compound. For example, phase one studies are generally conducted with healthy volunteers and emphasize safety, with the goal of determining any adverse effects of the drug in addition to how it is metabolized and excreted. Phase two studies focus on the efficacy of a potential new drug, defining the results in relative comparison to a placebo or control group. Phase three trials expand on both safety and efficacy, experimenting with different patient populations and dosages.
The many pitfalls on the road to a successful drug development have created new opportunities for pharmaceutical companies seeking to develop new compounds for different use-cases. Some of the world’s leading pharmaceutical compounds have been the result of re-positioned or repurposed medicines. For example, the popular side effect of sildenafil (Viagra), was stumbled upon during the phase I clinical trials for patients with hypertension and angina pectoris. After sildenafil was rejected in Phase two clinical trials for the treatment of angina, it was repositioned to navigate clinical trials as a potential treatment for erectile dysfunction. Over the last two decades, Viagra has consistently generated approximately US$1.8 billion in annual revenue.
Following in the footsteps of Pfizer (NYSE:PFE), pharmaceutical development companies are looking towards drugs that have previously reached the clinical trial stage as a means of advancing potential medicines in the most cost-effective manner possible. According to Algernon Pharmaceuticals (CSE:AGN,FWB:AGW,OTCQB:AGNPF) CEO Christopher J. Moreau, the process begins in analyzing an existing drug’s delivery mechanism and effects on the body. “Dr. Mark Willims, Algernon’s CSO, spent a number of years researching drugs that had never been approved in the US or Europe studying their targets and their mechanism of action. He developed a rationale for each drug as to why it might work in a new disease area,” he said. Algernon is a clinical-stage drug development company pursuing the repurposing of drugs targeting non–alcoholic steatohepatitis, chronic kidney disease, inflammatory bowel disease and idiopathic pulmonary fibrosis. The company also recently began to explore acute lung injury from serious lung disease including COVID-19.
The company’s approach is to take existing approved and genericized drugs and to screen them in globally accepted animal models for new diseases, filing new intellectual property rights as the company moves into off label trials in its country of origin. The company is currently working to develop a portfolio of 4 drug candidates in an effort to efficiently develop new treatments while mitigating initial risk factors. “Drug repurposing is a highly capital efficient model of drug discovery if it is done right. If successful it can bring an old drug into a new use approval within a three to four year period, adding 10 years to its new patent life. Risk of phase two and phase three failures are reduced because the drug is already proven safe, which is a considerable advantage as safety accounts for approximately 25 percent of phase two and phase three failures with new drugs,” said Moreau.
Algernon is one of many organizations investigating the potential in repurposing existing drugs. According to The Guardian, the Anticancer Fund has identified almost 300 drugs that studies suggest could hold anticancer properties, none of which have been specifically approved for cancer. Similarly, Cancer Research UK, a charity based in London, is now conducting clinical trials of both aspirin and metformin to help treat different types of cancers.
Considering the significant obstacles on the path to new drug development, drug repurposing enables pharmaceutical companies to leverage existing data to improve the efficiency of the clinical trial process. By mitigating trial risks, pharmaceutical companies are improving their chances of finding a potential breakthrough with a new use-case.
This article was originally published by the Investing News Network in April 2020.