Google blogger no longer allows me to respond to comments in my own blog. I am obliged to respond, if needed, in a separate blog . . . .Progress!
I wanted to respond to the anonymous correspondent to my previous blog who suggested that the recently approved antibiotics were just incremental improvements over previous drugs and therefore that they deserved the market response they achieved.
Incremental, apparently, is in the eye of the beholder. During my early years as an infectious diseases physician, a new B-lactam (but a B-lactam nevertheless) was undergoing phase 3 clinical trials. My surgical intensive care unit was closed because of an outbreak of Gram-negative (Serratia) infection resistant to all marketed antibiotics except colistin. I was able to procure this new B-lactam (imipenem) under a compassionate use program at Merck. It was miraculous and saved lives that would have otherwise been lost. But it was just another B-lactam – or was it? Is a new B-lactam-B-lactamase inhibitor combination active against KPC-bearing carbapenem-resistant Gram negative pathogens incremental? Is a non-B-lactam B-lactamase inhibitor not innovative? I would also note that the most innovative antibacterial compounds and strategies will be the most challenging to develop from both a regulatory and a commercial point of view (see this link).
Thanks for your reply. The incremental improvement comment is aimed toward the new products at Achaogen, Tetraphase, Entasis, and Melinta, as well as tedizolid. In each case, existing classes have been modified to provide some incremental improvement over existing products in the class. All of the examples have the burden of providing some significant advantage over generics in order to justify placement on the formulary as well as a higher price. Tedizolid may be more convenient and less toxic than linezolid, but do these features justify a formulary for choosing one over the other? Eravacycline has advantages compared to tigecycline; will these justify the price differential?
ReplyDeleteI completely agree that the most innovative compound and strategies will be the most challenging, and this is another reason that the needs of the industry are a mismatch for small biotech. In sum, small biotech has the capacity only for incremental improvements, and these will be marginal products, thus reflecting the low market values for the companies in this space. Likewise, the high innovation needed requires substantial costs and longer timelines: yet another mismatch for small biotech.