At one year (52 weeks), the ACR-20 response rate for apremilast is fairly close to what's been observed in clinical trials for the biologics: 50 percent for Enbrel, 57 percent for Humira, and 58 percent for Remicade). Of course, it is always difficult to compare results across different clinical trials.
The apremilist data are not without flaws and questions. Response rates measured by ACR-50 scores (a more stringent measure of response) are significantly higher for the biologics than for apremilast. In addition, for some unknown reason the ACR-20 scores for the higher 30 mg apremilast dose fell below the 20 mg dose at 52 weeks despite being higher at both of the previous time points. The response scores for apremilast are also not adjusted for placebo.
All caveats aside, the key points remains the deepening of response to apremiliast over time and that response rates are in the same efficacy ballpark as the biologics. As patients are followed beyond one year, response rates to apremilast may increase further.
Why does it matter that apremilast's efficacy gets close to the biologics? Because of the divergence between Celgene's sales expectations for apremilast and what investors and analysts currently model. Relatively modest Street numbers for apremilast paint the picture of a drug that has some efficacy but which will not be widely adopted by doctors and patients. Analysts derive these low from early efficacy data that put apremilast well below the biologics.
The improved response to apremilast over time changes this calculation.
It now looks like apremilast is an oral treatment option that can used for an extended period of time with a relatively benign adverse event profile. Over time, the efficacy of apremilast is comparable to the biologics. This makes apremilast a much more attractive treatment option for doctors and patients. Remember, apremilast is a pill; biologics require injections.
The updated apremilast data being presented at the rheumatology meeting in Europe this week should prod investors and analysts to raise their sales forecasts. If the Street's sales expectations for the drug align more closely with Celgene's own guidance, Celgene shares should also move higher.
Sobek is long Celgene.