Anthera Shifts Its Strategy For Blisibimod

2012 was a rough year for Anthera Pharmaceuticals (NASDAQ: ANTH) and its pipeline. The stock suffered from large drops in share price on two separate occasions, regarding two different drugs and two different events.

The first drop occurred on March 12th in reaction to the termination of the phase III VISTA-16 trial, which was evaluating the short-term performance of Anthera's drug A-002 in patients with acute coronary syndrome (ACS). The decision was made after a recommendation of termination by the Data Safety Monitoring Board (DSMB), citing that the drug was simply not effective enough to justify continuation of VISTA-16. The recommendation remains controversial due to statements from Dr. Stephen Nicholls, who oversaw the trial and suggested that the drug's efficacy was in line with expectation.

Anthera took another hit after June 27th, when its remaining pipeline drug blisibimod (also known as A-623) failed to meet the primary endpoint of a Phase IIb trial (PEARL-SC). The PEARL-SC trial was evaluating blisibimod for the treatment of systemic lupus erythematosus in adult patients that were already receiving a standard prednisone regimen. Although it was later revealed that blisibimod did positively affect some lupus patients' outcomes (measured by high scores on the SELENA-SLEDAI index) with statistical significance, patients who did not respond as well to blisibimod seemed to drag down the pooled results enough to make the overall trial a technical failure.

On the bright side, we now know that the patients that do respond to blisibimod do extremely well. Due to this, the European Medicines Agency (EMA) immediately gave Anthera the nod to progress to Phase III trials for an eventual Marketing Authorization Application (MAA). The FDA made the same decision after a couple of months which caused the stock to regain some of its losses, albeit briefly.

As we head into 2013, investors should note that Anthera's clinical development for blisibimod as a lupus drug has been put on temporary hold, despite its ability to move onto Phase III trials for the treatment of lupus. This is a new, strategic move by Anthera as they look for a partner for this particular program. An interesting observation in the PEARL-SC trial also sparked the company's new effort to develop blisibimod as a treatment for the orphan indication IgA nephropathy.

IgA Nephropathy (also referred to as Berger's disease) is a condition caused by a buildup of IgA antibodies in patients' kidneys. The cause of the disease is related to the protein BAFF, which is also blisibimod's target. Berger's disease has orphan indication in the United States since it affects only 40,000 or so people annually. High levels of BAFF are associated with more severe disease. One of the leading indicators for positive clinical outcomes in IgA nephropathy is a low level of proteinuria, and there is evidence that lowering proteinuria will improve patients' prognosis. Anthera observed a statistically significant drop in proteinuria in patients treated with blisibimod in the PEARL-SC trial, providing clinical evidence supporting the IgA nephropathy indication.

So, after a dramatic 2012, ANTH investors are greeted with another twist to the story to start off a New Year. Not only did the PEARL-SC trial ultimately allow Anthera to continue into Phase III trials for lupus (which will likely happen once a partner is found), but Anthera is pursuing a radically new direction as it develops blisibimod as a potentially lucrative treatment option for IgA nephropathy patients. Also note that blisibimod will also have no problem receiving orphan drug status for this indication, which will extend its exclusivity in the United States by two years as described in the PDUFA Act.

The market is not really giving ANTH enough attention to recover the stock following recent developments, although the orphan drug designation of blisibimod for a brand new indication (IgA nephropathy) should interest the same crowd that chased all the major orphan drugs in 2012.

Disclosure: I have no positions in any stocks mentioned, and no plans to initiate any positions within the next 72 hours. I wrote this article myself, and it expresses my own opinions. I am not receiving compensation for it. I have no business relationship with any company whose stock is mentioned in this article.