Abbott hepatitis C combo impressive in small study: is the new standard of care 95% in naives?
(Reuters) - A combination of experimental oral hepatitis C treatments being developed by Abbott Laboratories led to cure rates higher than 90 percent in previously untreated patients, according to data from a small mid-stage study.
The data, to be presented at a major European liver meeting later this month, puts Abbott firmly in the crowded race to produce a short duration, interferon-free treatment regimen for the serious liver disease.
Abbott shares rose nearly 2 percent on a down day for the broader market. Shares of some companies developing rival drugs, such as Gilead Sciences Inc and Idenix Pharmaceuticals Inc fell.
"This demonstrates unprecedented cure rates for the most common form of hepatitis C infection. And we were able to achieve those rates with only a 12-week duration of therapy," said Scott Brun, Abbott's divisional vice president for infectious disease development.
Abstracts, or brief summaries, of studies to be presented at the European Association for the Study of the Liver (EASL) meeting in Barcelona were made available on Wednesday.
"At EASL it's going to be very clear that we've reached a really transformational moment for patients with HCV (hepatitis C virus)," Brun said.
The Phase II trial of previously untreated patients, known as Co-Pilot, combined Abbot's protease inhibitor ABT-450 boosted by the antiviral drug ritonavir with its polymerase inhibitor ABT-333 and ribavirin, a drug that is part of all current hepatitis C regimens.
Patients received the combination therapy for 12 weeks and were checked 24 weeks later for signs of the virus in the blood to determine if there was a sustained virologic response, or SVR. Any patients that achieved an SVR 24 weeks after completing treatment are deemed to be cured.
Eighteen of the 19 patients who received a 250 milligram dose of ABT-450 as part of their combination achieved SVR, or 95 percent, while 13 of 14 patients who got a 150 mg dose of ABT-450 were deemed to be cured, or 93 percent.
"We would acknowledge that the 4-drug combination from Abbott sets a high bar for competitors," BMO Capital Markets analyst Jim Birchenough said in a research note.
He noted that Gilead shares were down in response to the Abbott data, but expressed confidence that a Gilead combination therapy will ultimately be able to match Abbott's efficacy.
In a third arm of the study that involved patients who had failed to be helped by the former standard treatment of interferon and ribavirin, eight of 17 patients achieved SVR for a cure rate of 47 percent.
"In our view, the response rate in previous non-responders may not be competitive," said Wells Fargo analyst Larry Biegelsen, who called the treatment naive data "very strong."
Abbott is also testing a drug from a promising class known as NS5A inhibitors in various all-oral combinations that it believes may improve cure rates for prior non-responders.
"For a first step it's very encouraging," Brun said of the new data in non-responders. "If you're able to add the potent NS5A inhibitor into the mix we think there's the potential to do even better and that's currently under study."
There were no serious side effects seen in the study, with the most common side effects fatigue, nausea and headache.
The treatment of hepatitis C took a major leap forward last year with the approval of new drugs from Vertex Pharmaceuticals Inc and Merck & Co that led to far-higher cure rates with the potential for shorter treatment durations than interferon and ribavirin, which had to be taken for 48 weeks and cured about 40 percent of patients.
Vertex's Incivek led to cure rates as high as 80 percent in previously untreated patients. But both new drugs must be taken with interferon and ribavirin, and the shortest treatment regimen is currently 24 weeks, with many patients still requiring 48 weeks.
Interferon, an injected drug, causes miserable flu-like symptoms that lead many patients to discontinue treatment and many more to put off treatment altogether. If left untreated, hepatitis C can lead to cirrhosis, liver cancer, and death. It is also the most common reason for liver transplants.
Analysts believe an interferon-free therapy with a high cure rate and shorter treatment duration is likely to be a multibillion-dollar seller. That has led to fierce competition among drugmakers.
Gilead and Bristol-Myers Squibb Co recently spent billions to buy companies developing such drugs. Vertex, Merck and several other smaller companies are also working on various interferon-free combinations.
Gilead shares were down 2.5 percent at $46.88, while shares of Idenix were off more than 11 percent at $9.09. Abbott shares were up 0.4 percent at $61.40 after climbing to a multi-year high of $62.55 earlier on Wednesday.
Far larger trials will be needed to confirm the efficacy and safety of the Abbott drugs, and the company said it is on track to begin pivotal Phase III testing in early 2013.
But the data Abbott will present at EASL this month clearly signals that it intends to be a major player in the field.
Abbott Drugs Suppress Hepatitis C Virus In 2 Studies
--Abbott is testing several experimental hepatitis C drugs
--More than 90% of patients with no prior treatment in one study had suppressed virus 12 weeks after treatment
--Abbott is targeting launch of hepatitis C regimen in 2015
(Updates with analyst reaction in third paragraph, stock prices for Abbott in fourth paragraph and for some rivals in final paragraph)
By Peter Loftus
Of DOW JONES NEWSWIRES
Experimental drugs from Abbott Laboratories (ABT) suppressed the hepatitis C virus in most patients in two small, mid-stage studies.
The results unveiled Wednesday could reinforce Abbott's position as a key player in an industry race to bring the next generation of drugs to what is expected to be a multibillion-dollar market for hepatitis C therapies. The drugs' safety and efficacy, however, need to be confirmed in additional studies.
"The Abbott data are clearly impressive from an efficacy perspective," said ISI Group analyst Mark Schoenebaum.
Abbott shares rose 46 cents, or 0.7%, to $61.58 in recent trading, and earlier set a 52-week high of $62.57.
Abbott has said it could begin selling a new hepatitis C regimen in 2015, and sales could eventually exceed $2 billion annually. The drugs would be sold by the pharmaceutical business that Abbott plans to split off into an independent company later this year, to be named AbbVie.
Summaries of the Abbott studies and studies of other liver-disease drugs were posted online Wednesday by the European Association for the Study of the Liver, or EASL, in advance of its annual scientific meeting in Barcelona in mid-April. Some EASL study summaries won't be released until the conference begins.
Gilead Sciences Inc. (GILD), Bristol-Myers Squibb Co. (BMY), Vertex Pharmaceuticals Inc. (VRTX) and Merck & Co. (MRK) are among other companies developing hepatitis C drugs to tap a market that research firm Decision Resources predicts will hit $16 billion in 2015, up from just $1.7 billion in 2010.
Hepatitis C is a viral disease that attacks the liver, and is believed to afflict about 180 million world-wide, with more than 4 million in the U.S., according to the National Institute of Allergy and Infectious Diseases. At-risk groups include people who had blood transfusions before 1992, when a screening test for the virus was developed.
Abbott is developing several potential hepatitis C drugs. One of them, ABT-450, is a so-called protease inhibitor, which is the same class of drugs as two that went on sale last year, Merck's Victrelis and Vertex's (VRTX) Incivek, which is marketed outside the U.S. by Johnson & Johnson (JNJ) as Incivo.
The protease inhibitors advanced treatment of hepatitis C, but there is still room for improvement because current treatments require an injectable drug, interferon, that can be difficult for patients to tolerate. Abbott and other companies want to develop all-oral regimens that eliminate the need for interferon.
In addition, Abbott is developing two polymerase inhibitors, ABT-072 and ABT-333, which have different mechanisms of action than the protease inhibitors.
The two studies released Wednesday each focused on ABT-450. One, titled "Co-Pilot," involved 50 patients who were given the following: one of two different dose levels of ABT-450, combined in the same pill with Abbott's Norvir boosting agent; ABT-333; and an existing drug called ribavirin that is part of the current standard of care for hepatitis C. The regimen amounted to several pills taken daily.
The study tested safety and tolerability of a 12-week regimen of the drugs in people with the most common form of hepatitis C, known as genotype 1. Patients in the study either hadn't previously received any treatment or didn't respond to prior treatment.
In the treatment-naive patient groups, more than 90% had a sustained virologic response 12 weeks after the end of treatment, a measure known as SVR12. Sustained virologic response is roughly equivalent to being virus-free or having nearly undetectable viral levels.
In the patients who didn't respond to prior treatment, 47% achieved SVR12 in the Abbott-funded study.
The second, smaller study--called "Pilot"--combined ABT-450 boosted by Norvir, ribavirin, and ABT-072. All 11 patients had received no prior therapy. This group of patients had a subtype of the virus that generally responds well to an interferon-based regimen and thus considered among the easier forms to treat.
Ten of the 11 patients achieved a sustained virologic response 24 weeks after stopping treatment, for an SVR24 rate of 91%. One patient relapsed.
"We're showing a sustained, post-treatment response from 12 to 24 weeks out" from the end of treatment, said Scott Brun, divisional vice president of infectious disease development at Abbott.
In both studies, the most common adverse events included headache, fatigue and nausea, and most were mild. In the larger "Co-Pilot" study, four patients had severe adverse events including fatigue and vomiting. There were no deaths in either study.
Abbott is conducting large mid-stage studies testing various combinations of the three experimental drugs used in the smaller studies, Brun said. Abbott hopes to move some combination of the drugs into late-stage testing next year.
Abbott developed ABT-450 in collaboration with Enanta Pharmaceuticals.
Shares of some of Abbott's rivals in the hepatitis C field declined Wednesday. Idenix Pharmaceuticals Inc. (IDIX) dropped 6% to $9.62; Gilead was off 3% at $46.57; while Vertex and Bristol-Myers were each down less than 1%.