Faced with the increasing threat of antimicrobial resistance (AMR), experts are calling for more incentives to boost investment in new antibiotics.
At the FDA/CMS Summit in Washington, DC today, representatives from several companies developing new antibiotic treatments said that while recent initiatives such as the Generating Antibiotics Now Act (GAIN Act) have helped revitalize investment in antibiotic development, more needs to be done to encourage research and development.
The two biggest hurdles for antibiotics, according to the panelists, are poor economic returns compared to other life-saving drugs and not enough market incentives to justify investments.
Approving New Antibiotics
In 2012, the GAIN Act introduced the new qualified infectious disease product (QIDP) designation for antibiotic and antifungal drugs that treat "serious or life-threatening" infections. Products with QIDP designation automatically receive priority review from FDA and, if approved, "may receive five additional years of marketing exclusivity."
Speaking at the panel, Amanda Jezek, vice president of public policy and government relations at the Infectious Diseases Society of America (IDSA) called the GAIN Act an "important first step." However, Jezek said that other measures, such as the proposed limited-population antibacterial drug (LPAD) pathway in the House-passed version of the 21st Century Cures Act, could do more to boost research and development.
The proposed LPAD pathway would give sponsors of antibiotics intended to treat small patient populations more flexibility to rely on traditional and/or non-traditional endpoints in clinical studies, data from early stages of development such as "preclinical, pharmacologic, or pathophysiologic evidence," as well as data from Phase II trials to support approval.
Barry Eisenstein, a physician specializing in antimicrobials at Merck, pointed to a 2013 commentary he coauthored with infectious disease specialist John Rex, which proposed a four-tier system for determining how much data should be required to support antibiotic approvals.
|Four Tier Approach|
|Tier A||"Two controlled, adequately powered Phase III trials conducted for the initial indication, with data gathered across a range of susceptible pathogens."|
|Tier B||"Testing in a standard Phase III trial. This standard trial may well not enroll and patients infected with highly resistant pathogens, but the comparative safety database plus the clear demonstration that the [pharmacokinetic-pharmacodynamic] predictions are valid provides strong support for small supplemental datasets reporting efficacy in patients infected with highly resistant organisms."|
|Tier C||"Limitations on the number of patients who can be studied require that the human efficacy database be limited to small, prospective comparative trials, open-label datasets, and historical efficacy."|
|Tier D||Relies on the "Animal Rule" to support the approval of drugs to treat diseases such as Anthrax that cannot ethically be tested in humans.|
Reimbursement and Pricing
The panelists agreed that economics pose a major barrier to antibiotic development, saying that low levels of reimbursement and low prices overall make antibiotics a tough sell to investors.
The panelists said they would like to see a value-based pricing system for antibiotics as current payments do not reflect their life-saving potential. Not only are antibiotics inexpensive compared to other drugs, when used appropriately they have the potential to reduce hospital stays, bringing further savings to healthcare systems, they said.
In addition to getting new antibiotic drugs to market, the panelists called for more support for rapid diagnostics that can quickly and accurately identify infections.