Potential Sanfilippo Treatment, SLS-005, Advances as Orphan Drug in EU

The Committee for Orphan Medicinal Products, a branch of the European Medicines Agency (EMA), favors designating SLS-005 (trehalose) an orphan drug as a potential treatment for Sanfilippo syndrome, Seelos Therapeutics, its developer, announced.

The positive opinion will now be sent to the European Commission, which generally supports such recommendations, for a final decision expected by late August. European orphan drug designation would grant Seelos incentives such as protocol assistance, lower regulatory fees, and market exclusivity for 10 years.

Under European Union guidelines, an orphan disease is one that affects no more that 5 in every 10,000 people within the EU.

SLS-005 consists of a small sugar called trehalose, which is administered intravenously, or directly into the bloodstream. It is thought to promote autophagy — a natural cellular waste disposal process — within the cells of the central nervous system (the brain and spinal cord).

Specifically, SLS-005 is designed to enhance these cells’ ability to eliminate large sugar molecules called glycosaminoglycans, whose toxic accumulation is a key feature of Sanfilippo syndrome.

The U.S. Food and Drug Administration (FDA) granted SLS-005 both rare pediatric disease and orphan drug designations as a potential Sanfilippo therapy this year.

Positive results from preclinical studies in mice led the FDA to approve a request by Seelos to initiate a Phase 2b/3 trial of SLS-005’s safety, tolerability, and efficacy in patients with Sanfilippo types A and B. SLS-005 was seen to reduce inflammation in the brain and retina, lessened nerve cell degeneration, and extended the lifespans of the mice.

Seelos also recent announced plans to expand clinical studies to patients with Sanfilippo types C and D. The disease’s four types are each distinguished by a mutation in different genes used to make the enzymes necessary to break down glycosaminoglycans.

The company also plans to test SLS-005 in a European clinical study among patients with Sanfilippo syndrome types A and B.

Seelos is collaborating with Team Sanfilippo Foundation (TSF), a nonprofit organization founded by parents of children with Sanfilippo syndrome, in its efforts to develop SLS-005. TSF’s mission is to provide funding to support research into potential therapies and help families gain access to treatments and clinical trials.

The FDA and the EMA have also designated SLS-005 an orphan drug as a potential treatment of spinocerebellar ataxia type 3 and oculopharyngeal muscular dystrophy (OPMD).