Biogen Idec and PDL BioPharma
- Administered via intravenous infusion every four weeks; also studied in subcutaneous injections.
- Zenapax is a genetically engineered monoclonal antibody that binds to a specific receptor on T cells for interleukin-2 (IL-2), which plays a role in the activation of T and B cells. It results in a sustained but reversible reduction in activated T cells and reduces inflammation. It is approved by the FDA for use in rheumatoid arthritis and other autoimmune diseases.
- Participants in the Phase II CHOICE study had either RRMS or SPMS, with worsening disease activity while on interferon-beta therapy. The study showed that Zenapax was well tolerated when added to the interferon. A 25-percent reduction was seen in the frequency of enhancing lesions in the low-dose group (150 mg every four weeks), and a 72-percent reduction was seen in the high-dose group (300 mg every four weeks).
- The ongoing Phase II SELECT extension trial, with 600 participants, is scheduled for completion in September 2015. It is a one-year study that will assess the safety and immunogenicity (the incidence of the development of antibodies) of extended treatment with Zenapax. The study will assess adverse events, laboratory evaluations, vital signs, physical examinations, and the development of antibodies. Secondary outcome measures include the continuing response to treatment as measured by MRI and clinically (determining annualized relapse rate and the proportion of subjects who are relapse-free).