Isis Pharmaceuticals, Inc., a leading company in antisense drug discovery and development, exploiting a novel drug discovery platform, has dosed its first infant in the 12 mg dose group in the phase II study evaluating ISIS-SMNRx in infants with Type I spinal muscular atrophy (SMA). The phase II study is designed to allow Isis to define the optimal dose for the larger phase II/III study in infants and to provide safety and tolerability data.

Isis also plans to complete this study and initiate the larger phase II/III pivotal study early next year. Isis earned a $2 million milestone payment from Biogen Idec associated with the advancement of this study.

The phase II study of ISIS-SMNRx is an open-label, multiple-dose, dose-escalation pilot study, which will include eight infants who have been diagnosed with Type I SMA. To meet enrollment criteria, infants must be between the ages of three weeks and seven months, live in close proximity to a study site and pass screening evaluations conducted at study sites. The study is being conducted at centers in the United States and Canada.

"We continue to be very encouraged with the progress we are making with ISIS-SMNRx, and we are on track to begin our phase III programme early next year. We look forward to sharing the results from our multiple dose studies in infants with Type I SMA and in children with Type II and Type III SMA later this year or early next year," said C Frank Bennett, Ph.D., senior vice president of research at Isis.

ISIS-SMNRx is designed to alter the splicing of a closely related gene (SMN2) to increase production of fully functional SMN protein. The United States Food and Drug Administration (FDA) granted orphan drug status and fast track designation to ISIS-SMNRx for the treatment of patients with SMA. Isis is currently in collaboration with Biogen Idec to develop and potentially commercialize the investigational compound, ISIS-SMNRx, to treat all types of SMA. Under the terms of the January 2012 agreement, Isis is responsible for global development and Biogen Idec has the option to license the compound until completion of the first successful phase II/III study.

Isis acknowledges support from the following organizations for ISIS-SMNRx: Muscular Dystrophy Association, SMA Foundation, Families of SMA and intellectual property licensed from Cold Spring Harbor Laboratory and the University of Massachusetts Medical School.

Isis is exploiting its leadership position in antisense technology to discover and develop novel drugs for its product pipeline and for its partners.