Hydroxychloroquine. The world rallied around this old drug as a potential treatment of COVID-19 patients. The pharma industry, independent researchers, and governments rushed to conduct trials to see if hydroxychloroquine is safe and effective at any stage of this invasive virus. Though it has now been ruled ineffective for COVID-19 treatment by the FDA, hydroxychloroquine thrust the idea of novel uses for old drug products into the spotlight.
Indeed, the world is becoming intimately aware of the importance of repurposing existing drugs for new indications. The public is being reminded of the years of research needed for the development of a new drug – time we don’t have. Today, there are many drugs being tested to determine if they can be used to treat COVID-19 patients. The lay press is suggesting that repurposed drugs might be approved within months. In excess of 1000 trials are in progress, with some studies targeting the viral replication cycle to prevent progression of the disease and others attempting control the symptoms of the disease.
In short, drug repurposing is experiencing a surge in popularity and public awareness as the race to develop therapies to alleviate the COVID-19 crisis continues. Repurposed drugs, which are typically approved through the 505(b)(2) pathway, represent the best option for suppressing the pandemic quickly and offer several benefits to both sponsors and patients.
The Advantages of Repurposing Drug Products
Get treatments to patients sooner.
Speed to patients is the most critical advantage of repurposing for COVID-19 therapies. Hospitals remain overwhelmed with patients who have contracted a virus for which no reliable treatments exist. The abbreviated development timeline associated with repurposing drugs could substantially accelerate the delivery of treatment to afflicted patients.
Rely on safety information from existing drug products.
The primary reason that repurposed drugs have shorter development programs is that sponsors can rely on existing drug safety data for an NDA. Because the safety of the drug product has already been proven, typically fewer studies are required. Additionally, clinical trials to determine if a repurposed drug can halt disease progression can be relatively short-term and inexpensive since researchers generally know the safety profile and have a good idea of the proper dose and duration. Regulators will approve such drugs if several studies show consistent benefit when weighed against the observed side effects. Progress is being made with several candidates.
Reduce the cost of drug development programs.
These shorter development timelines and streamlined studies lead to significant cost savings for the sponsor. Moving rapidly to the clinic with so many unanswered questions about efficacy carries considerable risk, and the scale of manufacturing needed for COVID-19 therapies is enormous. Especially in an uncertain funding environment, having a cost-optimized strategy for a well-understood active ingredient could enable a program to progress to approval or authorization.
Existing vs. Differentiated Drugs
There is a large difference between the effort needed to repurpose a drug that can halt disease progression of COVID-19 and the effort needed to address the debilitating conditions post-recovery.
The first are simply trials with the existing drug and can be the quickest way to deliver therapies to patients, though the sponsor often ends up with an additional indication on the label but little financial reward. One such product is remdesivir (originally developed to treat Hepatitis C and RSV and researched as a treatment for Ebola), for which the FDA has issued an Emergency Use Authorization to treat patients with severe cases of COVID-19.
On the other hand, treating COVID-19 survivors with debilitating conditions usually requires changes in the dose, administration, route, or molecule itself. In these cases, often only abbreviated or even PK-only programs are required. The resulting new, differentiated product can offer a profound benefit for patients and, often, substantial financial reward for the sponsor.
An example is a planned trial by PureTech Health Plc of deupirfenidone, for the potential treatment of serious respiratory complications, including inflammation and fibrosis. Deupirfenidone is deuterium-substituted analogue of pirfenidone, the active ingredient found in Roche’s idiopathic pulmonary fibrosis treatment Esbriet®. Esbriet itself might be effective in this indication, but it has some limitations due to hepatotoxicity and its short half-life. Deupirfenidone, or LYT-100, provides the efficacy of pirfenidone without the tolerability issues.
In the race to treat COVID-19 and other life-threatening and life-altering diseases, investing in repurposing drugs can result in a significant savings of cost and years earlier to the patient than traditional drug development. Contact Camargo to discover how our multi-disciplinary team can rapidly advance your program and gain approval or authorization for your repurposed drug product.