Celgene (NASDAQ:CELG) has two goals for its multiple myeloma drug, Revlimid: to have patients begin taking it earlier in the progression of their disease, and to have them stay on the drug longer. It made progress on the latter with data presented at the American Society of Hematology’s annual meeting yesterday, but whether the drug should be used early in disease progression remains to be seen.

Revlimid is currently approved to treat patients who have failed one treatment already. The company is testing the drug in newly diagnosed multiple myeloma patients in order to capture more patients, especially in Europe, where doctors aren't as likely to use the drug off-label.

The trial had three treatment groups. One group got standard chemotherapy drugs melphalan and prednisone (MP); the second got melphalan, prednisone, and Revlimid (MPR); and a third got MPR and stayed on Revlimid as a maintenance drug (MPR-R).

The good news is that MPR-R worked much better than either MP or MPR; adding a maintenance phase reduced the risk of progression or death by 75% compared to MPR alone. This is good news for Celgene.

Drugs like Pfizer's (NYSE:PFE) Lipitor, sanofi-aventis' (NYSE:SNY), and Bristol-Myers Squibb's (NYSE:BMY) Plavix -- and even up-and-comers like Merck's (NYSE:MRK) Januvia -- do so well for those companies because they have to be taken month after month. Getting to that point with Revlimid via maintenance-phase sales will clearly help Celgene.

The data on using the drug early in disease progression is a little more complex. The MPR patients didn't look much different than the MP patients in the preliminary results, suggesting that Revlimid might not be helping early in the disease progression. Patients might fare just as well with chemotherapy alone, or perhaps chemotherapy plus rival drug Velcade from Takeda and Johnson & Johnson (NYSE:JNJ), followed by Revlimid maintenance therapy.

The problem here is that comparing MP to MPR isn't very useful if doctors are going to use Revlimid as a maintenance drug. Instead, a better comparison would have been MPR-R to MP-R -- chemotherapy alone and then Revlimid maintenance.

MP-R was conspicuously missing from the trial, though. Wonder if Celgene designed the trial with an all-or-nothing goal in mind?