treat pneumonia and skin infections, generated $1.3B in revenues last year, but this was achieved relatively slowly and has flattened with only 3.5 years of patent life left. Compare this with the situation at Cubist, which reported about $800 million in revenues last year, largely from the sales of daptomycin (Cubicin). Growing Cubist’s revenue by five percent would necessitate generating only about $40 million in new revenues. That can be achieved by the second year on the market for a reasonably differentiated hospital antibiotic. Daptomycin generated $59 million in revenue in its second year on the market in 2004). With approximately another six years of patent life left, Cubicin could generate revenue growth for Cubist that scales appropriately with the company’s size. Scaling revenue potential to the market is critical to companies and their investors.
Secondly, under the current FDA regulatory paradigm, achieving that $1 billion in peak sales would require any company to make an enormous investment in multiple sets of expensive, global Phase 3 trials. Antibiotics are the only therapeutic area in which multiple sets of registration-quality Phase 3 trials are necessary to gain full market potential. As an example, under the current regulatory paradigm in the U.S., a new agent for treating methicillin-resistantStaphylococcus aureus (MRSA) would have to undergo 6 Phase 3 trials—2 each in skin, lung and bacteremia—to be labeled for those indications even though MRSA is the common pathogen in each. Is there any wonder why large pharmaceutical companies have backed out of this area when they can deploy their development dollars in more lucrative therapeutic areas? The GAIN Act does not address this critical issue.
Nevertheless, there is a glimmer of hope in terms of addressing this issue in provision 5, “Pathogen-focused drug development.” Should the FDA truly revamp the antibiotic approval process in a manner that is more consistent with how clinicians treat patients—i.e. by the type of pathogen causing the infection rather than by what body part the pathogen happens to reside in—we would likely see an enthusiastic response from clinicians, patients, companies and investors. There is precedence for this in Japan where, in the case of MRSA, a single “all comers” Phase 3 trial is conducted that enrolls patients with MRSA skin, lung and bacteremia infections. This single trial enrolls much faster, is significantly less expensive to conduct and gets new antibiotics in the hands of clinicians and their patients much faster.
Are Japanese regulatory authorities more cavalier about the treatment or safety of patients? Of course not. As part of the approval process, all prior clinical and non-clinical supportive data are reviewed and must be consistent with efficacy and safety in the targeted indications. One important advantage that antibiotics have is that such early nonclinical data are highly predictive of Phase 3 results. If this is recognized and adopted in the FDA’s guidance in time to address the growing epidemic of multidrug-resistant infections, the U.S. populace will experience a truly meaningful “gain.”
