OP-101 is an experimental medication developed by Orpheris to treat adrenoleukodystrophy (ALD). OP-101 received orphan drug status from the U.S. Food and Drug Administration (FDA) in November 2017.

How OP-101 works

ALD is a rare genetic disorder characterized by the buildup of saturated very long-chain fatty acids (VLCFAs). The buildup of these compounds causes a loss of the myelin sheath — the protective protein coat surrounding the nerve fibers. Without this coat, the nerve fibers become fragile and are easily damaged, which results in neurodegeneration.

OP-101 is designed to prevent neurodegeneration by reducing inflammation in areas of the brain affected by the disease. It is a anti-inflammatory therapy that is covered by a protective coat of another compound that makes the treatment inactive until it reaches inflamed areas of the brain. Once taken up by an inflamed cell, the protective covering is removed, and the anti-inflammatory treatment is released to act on directly on the cell.

Pre-clinical studies in rodent and primate models have shown that the compound can be successfully targeted to areas of brain inflammation.

OP-101 in clinical trials

OP-101 was recently tested in a Phase 1 safety study (NCT03500627) in healthy volunteers. Eight participants were treated with 20, 40, or 80 mg of OP-101 per kilogram of body weight, administered as an infusion into the bloodstream over one hour. The primary outcome measured was adverse events during infusion or afterward. Patients were monitored for 15 days. Pharmacokinetics (how quickly the body uses the treatment) were also evaluated. The results of this trial have not yet been published.

Orpheris is planning to continue testing the treatment in Phase 2 and Phase 3 clinical trials with about 30 participants.


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