Antisense Therapeutics announced positive results from a phase 2 open label trial evaluating ATL102 in nine non-ambulant patients with DMD aged between 10 and 18 years. The trial was conducted at the neuromuscular center of the Royal Children’s Hospital (RCH) in Melbourne, Australia. The trial met its primary endpoint confirming the safety and tolerability of ATL102 for advancement into a potentially pivotal Phase IIb clinical trial. The final trial results have also confirmed the drug’s positive effects on the secondary trial endpoints that assessed the drug’s activity and efficacy including measuring the effects on immune cell numbers in the blood and measuring the participants’ functional capacity as evaluated via Performance of Upper Limb Test (PUL2.0), grip and pinch strength and distal mobility (using the MyoSet, MyoGrip, MyoPinch and MoviPlate tools, respectively).
The primary objective of the ATL1102 trial was to assess the safety and tolerability of 25 mg of ATL1102 administered once weekly (subcutaneous injection) for 24 weeks. ATL1102 was assessed to be generally safe and well tolerated. No serious adverse events were reported, and no patients withdrew from the study. The most common adverse events were injection site erythema and skin discoloration.
In addition, improvement and stabilization was observed across different measures of motor function & strength. Activity on the targeted CD49d immune cells was consistent with drug’s proposed mechanism of action and new MRI data suggests stabilization of percentage of fat in muscles and preservation of functional muscle mass.
Antisense has made a submission to the European Medicines Agency for Scientific Advice on a Phase IIb trial design. The Company is also in the process of preparing submissions for Orphan Drug Designation for ATL1102’s use in DMD in the US and the EU.
ATL1102 is an inhibitor of CD49d expression on certain immune cells (e.g. T lymphocytes). It has been reported in research literature that patients with DMD who have a greater number of CD4+ and CD8+T lymphocytes with high levels of CD49d have more severe and rapid disease progression. ATL1102 is the only drug in clinical development for DMD targeting CD49d.