Could patients suffering from chronic lymphocytic leukemia, or CLL, benefit from not just one but two potential "wonder drugs" by the end of 2014?
Last week's surprising announcement from Gilead Sciences (NASDAQ:GILD) just might mean that the answer to that question is "yes." Gilead halted a late-stage study of experimental drug idelalisib targeting treatment of CLL. In most cases, stopping a study early isn't good. For Gilead, though, this was great news. The study was halted because idelalisib was so effective that there was no need to continue.
Gilead's success could position the company to be a close second in reaching the market with a new CLL drug. Pharmacyclics (UNKNOWN:PCYC.DL) and Johnson & Johnson (NYSE:JNJ) submitted a New Drug Application, or NDA, for ibrutinib in June.
Two lines of attack
While several treatment options exist for CLL, many patients either relapse or eventually don't respond to available treatments. Ibrutinib and idelalisib bring new approaches to battle the blood cancer, which is the most common form of leukemia in adults.
Pharmacyclics and J&J focused on inhibiting the Bruton's tyrosine kinase, or BTK, enzyme. The BTK enzyme plays an important role in B-cell receptor signaling, which is believed to help spread B-cell malignancies such as CLL. In a phase 2 study, the overall response rate for patients taking ibrutinib was 71% with an estimated 75% progression-free survival rate at 26 months.
Gilead took a similar yet different path with idelalisib. The drug inhibits the phosphoinositide 3-kinase, or PI3K, delta enzyme rather than the BTK enzyme. PI3K delta signaling is overly active in B-cell malignancies like CLL. Specific results haven't been released yet from Gilead's late-stage study of idelalisib, but they are undoubtedly very positive for the study to have been stopped early.
Ibrutinib is in the lead position for approval. The U.S. Food and Drug Administration is scheduled to announce a decision by the end of February 2014.
Efficacy doesn't seem to be a barrier for getting a green light. There were some adverse events during mid-stage studies, however, that could possibly raise some safety concerns. Severe reactions experienced by patients included pneumonia, dehydration, anemia, neutropenia, and thrombocytopenia, with six out of 85 study participants discontinuing treatment due to adverse events. These issues probably won't be showstoppers, though.
At this point, idelalisib looks to be around six months behind its rival from Pharmacyclics and J&J. Gilead submitted an NDA for the refractory indolent non-Hodgkin's lymphoma indication in September, but the biotech is still in early discussions with the FDA about an approval pathway for CLL.
While ibrutinib and idelalisib will compete against each other, the market is big enough to support both. Goldman Sachs pegs peak sales for ibrutinib for CLL at $5 billion per year. Oppenheimer sees peak sales for idelalisib hitting at least $700 million annually for the CLL and non-Hodgkins lymphoma indications.
Wondering about opportunities
With two "wonder drugs" for CLL potentially on the market next year, investors might be wondering what opportunities might still be available to profit. In my opinion, Gilead is a smart pick even without the recent good news about idelalisib. The biotech is well positioned to be a leader in the lucrative hepatitis C market and is still growing its juggernaut HIV franchise.
As for J&J, I agree with what my fellow Fool Brian Orelli said: "Johnson & Johnson stock is always a buy (if you hold long enough)." Like Gilead, J&J also has a horse in the hep-C race with simeprevir. Of course, there are plenty of other things to like about the company. J&J didn't become one of the most highly valued companies on the planet by accident.
What about Pharmacyclics? The stock has more than doubled this year and now has a market cap of more than $9 billion. That sounds expensive for a company with no drugs currently on the market. However, if the analysts are even close to accurate about their outlook on ibrutinib's prospects, this stock still has plenty of room to run.
My view is that CLL patients are likely to see two new great treatment options available next year. I also think that investors buying stock in any or all of the companies behind these two drugs are likely to see great returns over the next several years. Wonders never cease.