Isis Pharmaceuticals Announces Positive Phase 2 Results In Patients With Spinal Muscular Atrophy

Shares of Isis Pharmaceuticals (ISIS) were up as much as 8% at one point today after the company reported positive phase 2 results form its Spinal Muscular Atrophy -- SMA -- study. A total of 20 infants were dosed with either 6mg or 12mg of ISIS-SMNrx. At the time of these results only 19 infants completed treatment with ISIS-SMNrx drug, so only 19 patients were evaluated for efficacy. 

Endpoints in the clinical study were: 

1. Event Free Survival - defined as the amount of time to permanent ventilation or death
2. CHOP-INTEND motor function scores - muscle movement established in the infant 
3. Other developmental milestones

The results showed a positive trend. Infant median-free events went from 16.3 months to 19.9 months for at least four infants in the 6 mg group. Infant median-free events went from 11.6 months to 16.7 months. In terms of the motor function scores, the infants all improved motor function scores from baseline. In addition the infants achieved other positive developmental milestones as well. The best part about the results were that there were no deaths since last efficacy evaluation. 

There was one infant that was required to be put on permanent ventilation from the 12 mg cohort group. In addition, for this drug to be efficacious it has to be well tolerated as well. There were no serious adverse events with ISIS-SMNrx at these doses given.

SMA is a rare genetic disease that affects a patient's ability to properly maintain survival of the motor neurons in the spinal cord needed for survival. There are no treatments today that are approved to treat SMA at all. That means ISIS would be the first for SMA approval upon phase 3 completion and be the first to potentially help these patients with no other treatment options.