Ofatumumab

What are the results so far?

An initial phase II trial evaluated ofatumumab given as an intravenous infusion; the drug is now being developed as a subcutaneous injection.

Intravenous infusion

In a phase II clinical trial, 38 participants received 2 ofatumumab infusions (100 mg, 300 mg, or 700 mg) or placebo 2 weeks apart. After 24 weeks, the participants first treated with placebo were treated with ofatumumab and patients who were initially treated with ofatumumab received placebo. All patients were then followed for an additional 24 weeks.

Ofatumumab treatment produced a major reduction in B cell numbers. For all doses of ofatumumab, there was almost complete suppression of new active lesions seen on MRI.

Subcutaneous injection

• MIRROR - ofatumumab compared to placebo

232 participants took different doses of ofatumumab (3 mg, 30 mg, or 60 mg given every 12 weeks; 60 mg every 4 weeks, or placebo) for a 24-week treatment period. The main measure of the study was the number of new active MRI lesions at week 12. All doses resulted in 65% reduction in new active MRI lesions. Based on data collected from weeks 4 to 12, those taking cumulative doses of at least 30mg showed more than 90% reduction in new active MRI lesions.

• ASCLEPIOS I - ofatumumab compared to Aubagio (teriflunomide)
• ASCLEPIOS II - ofatumumab compared to Aubagio (teriflunomide)

These phase III studies involved 1,882 people with relapsing remitting MS. Participants took either ofatumumab by subcutaneous injections every four weeks or Aubagio (teriflunomide) once daily for up to 2.5 years. In both studies, relapse rates were significantly lower for those taking ofatumumab. For the groups taking ofatumumab, the annual relapse rates were 0.11 and 0.10, a reduction of 50-59% compared to Aubagio. Ofatumumab also significantly reduced disability worsening which remained for 3 months and 6 months by 34% and 32% respectively. There was an indication that those taking ofatumumab were more likely to have an improvement in disability levels, although this was not statistically significant.