Big Setback for Trubion - Analyst Blog

Recently,

(

) announced that its partner,

(

) has decided to halt the development of Trubion’s lead candidate TRU-015 (PF-05212374). The candidate, in mid-stage studies, was being developed to treat patients suffering from rheumatoid arthritis (RA).

The decision to discontinue the development came after TRU-015 failed to meet the main goal of a mid-stage trial. The mid-stage study evaluated the safety and efficacy of TRU-015 against placebo. Even though TRU-015 was well tolerated, the combination of TRU-015 and methotrexate did not prove to be more effective than the placebo and methotrexate in treating RA patients.

The study failed to meet its primary endpoint of a 20% difference in response versus placebo. A higher than usual response rate among patients in the placebo arm was observed. However, Pfizer has not pulled the plug on Trubion’s other RA candidate, SBI-087 (PF-05230895), which is also undergoing mid-stage studies.

As a reminder, Trubion signed a collaboration agreement with Wyeth in 2005 for the development and global commercialization of TRU-015, and other therapies directed to inflammatory cells known as CD 20, including SBI-087. Pfizer inherited the CD20 collaboration after its acquisition of Wyeth last year.

Even though Pfizer’s decision to dump Trubion’s lead RA candidate is a blow to the company, its decision to continue the development of Trubion’s next-generation candidate SBI-087 is encouraging.

RA, an autoimmune disease, is estimated to affect approximately 5.2 million people in the United States, Japan and Europe. In 2009, total reported worldwide sales of protein therapeutics used for the treatment of RA exceeded $10 billion. Since approximately two-thirds of the RA patient population experience pain, stiffness and fatigue on a daily basis notwithstanding the administration of currently available treatments, we believe that there is a large unmet medical need in the RA market.

Even if SBI-087 manages to clear the developmental and regulatory hurdles to hit the market, it will face stiff competition from existing RA therapies such as

(

) and

(

) Rituxan,

(

) Orencia,

(

) Enbrel, Johnson and Johnson’s (

) Remicade and

(

) Humira.