Whether you realize it or not, we're in the middle of a very transformative period for treating hepatitis-C.
Before May 2011, the primary standard of treatment for hepatitis-C, a disease of the liver that can lead to cirrhosis of the liver or liver cancer and affects an estimates 150 million people worldwide, was peginterferon alfa and ribavirin. This therapy often gave patients nasty side effects, such as feeling you have the flu for 48 straight weeks, and induced a response in less than 50% of patients.
Source: Business Wire via Vertex Pharmaceuticals.
Times are rapidly changing
Then along came Vertex Pharmaceuticals (VRTX 4.55%) with Incivek. Although it still needed to be administered in combination with interferon, Incivek was a pill, and it marked a rapid turning point in researchers understanding of the hep-C virus, how to treat it, and how to improve patient quality of life. With Incivek, hepatitis-C patients went from less than a 50% chance of responding to a sustained virologic response after 24 weeks (i.e., no detectable levels of the virus) of 79% -- a clean 20% to 45% better than the previous standard of treatment. Not surprisingly, Vertex's Incivek quickly rose to the rafters and became the quickest drug to go from launch to $1 billion in lifetime sales ever!
But the hits just kept on coming, even after Vertex brought Incivek to market. In 2012 we finally got a good look at just how quickly hepatitis-C treatment options were expanding when we received mid-stage clinical study results of Gilead Sciences (GILD 1.91%) sofosbuvir and AbbVIe's (ABBV 0.81%) direct-acting antiviral combo drug. For Gilead, sofosbuvir delivered a perfect SVR after just 12 weeks in 25 of 25 patients. AbbVie's mid-stage study was a bit more expansive but proved just as exciting, with 77 of 79 patients experiences an SVR after 12 weeks.
In other words, in a two-year timespan we've seen the current standard of treatment go from a less than 50% response rate, to a 79% SVR over 24 weeks, to near perfection in a mid-stage trial for two separate companies in just 12 weeks' time. Furthermore, both sofosbuvir and AbbVie's DAA combo drug are all-oral pills that require no interferon -- and no interferon means fewer side effects! At the moment, sofosbuvir is currently under review by the Food and Drug Administration for possible new drug approval, while AbbVie's DAA combo is in late-stage trials, although it's received the highly coveted "breakthrough therapy" designation.
Two companies getting left in the dust
But it's not all fun and games for every company in the hepatitis-C sector. And I know what you're thinking – you're expecting me to point the finger at Bristol-Myers Squibb for its absurd purchase of Inhibitex in January 2012 for $2.5 billion and rake it over the coals once again. I'm not going to do that this time, because there are, in fact, two companies in far worse shape that, no matter how hard they try, can't seem to keep their foot in the door.
The first is Achillion Pharmaceuticals (ACHN +0.00%). At this time last year it looked as if Achillion could have a novel oral therapy on its hands to treat hep-C known as sovaprevir (previously ACH-1625). Following Bristol-Myers' BMS-986094 disaster, nucleotide-based inhibitors were expected to come under increased scrutiny while protease inhibitors like sovaprevir were expected to shine.
In July of this year, that house of cards came tumbling down, when the FDA placed a clinical hold on sovaprevir following an early stage study of drug-to-drug interactions with atazanavir. Though no serious adverse events were reached in the trial, ALT liver enzymes rose, causing the FDA to place the drug on clinical hold until further notice. Then came word just this Friday after the bell that the FDA had decided to continue its clinical hold on sovaprevir, even though Achillion noted in its press release that it met all of the FDA's requests in its previous clinical hold letter. Achillion does have three other experimental HCV drugs in its pipeline, but sovaprevir is, without question, its most promising candidate.
The second company, and perhaps the most unlucky biotech ever, is Idenix Pharmaceuticals (NASDAQ: IDIX), which is no stranger to the FDA's clinical hold process. It all began in 2010, when Idenix's lead compounds IDX184 and IDX320 were placed on clinical hold by the FDA. IDX184 would eventually be allowed to continue on while IDX320 was scrapped. In 2012, IDX184 was placed on clinical hold yet again along with IDX19368 following the death of a patient on Bristol-Myers' BMS-986094. Both of Idenix's experimental nucleotide-based therapies worked along the same pathway as BMS-986094, so the FDA decided to halt their study as well. Not too long after, Idenix would scrap both of these drugs. Finally, and to rub salt in the wound, earlier this year the FDA placed a clinical hold on its now lead drug IDX20963 until the company turns in additional preclinical safety data on the drug. It'd almost be a comical malady of events if it wasn't true!
The stark truth of the matter is that even if Achillion and Idenix manage to get their lead compounds off clinical hold, sofosbuvir and AbbVie's DAA-combo drug will more than likely make it to market two or three years before either sovaprevir or IDX20963 would even get reviewed by the FDA. Even though there's a wide moat of opportunity in treating hep-C, the window of opportunity for both companies is closing rapidly. In other words, if they don't get their foot in the door within the next 12 months, I'd just as soon lock the door of opportunity and throw away the key!
