GlaxoSmithKline has decided not to take an option on Ionis’ inotersen for polyneuropathy, further evidence of GSK’s retreat from the rare disease arena.
In a statement, antisense specialist Ionis said that GSK had taken the decision as a result of “a reprioritisation of its pipeline and strategic review of its rare diseases business”. Last week, the big pharma group said it was considering a sale of its rare disease unit as part of sweeping changes to its R&D operations.
In May Ionis reported the results of phase III trials of inotersen in familial amyloid polyneuropathy (FAP) and transthyretin (TTR) TTR amyloidosis polyneuropathy. The drug met the primary objectives of reducing neuropathy impairment scores – suggesting it was effective in delaying symptom progression – and improving patents’ quality of life.
The trial also revealed side effects that according to analysts could make regulatory approval a challenge – particularly as the FDA had previously placed the drug on a clinical hold because of thrombocytopenia.
That decision prompted GSK to hand back rights to the programme, although it retained an option to buy back in which it has now relinquished, along with an option on another Ionis candidate – IONIS-FB-LRX for complement-mediated diseases in early-stage clinical testing.
While the decision by GSK wasn’t a big surprise given the question mark over the drug and the drugmaker’s shifting priorities, analysts at Leerink have suggested Ionis could now find it harder to prepare for a potential launch of inotersen, which is due to be submitted for approval in the EU and US later this year.
Ionis said it was ‘pleased’ to regain rights to the two drugs, indicating it would file for use of inotersen in polyneuropathy due to hereditary TTR amyloidosis in the first instance. To that end, it is looking at building up a commercial subsidiary to sell the drug in North America – along with “other options” which could include another commercial partner.
With a view to enticing other potential partners, Ionis said it is accelerating the development of a follow-up drug to inotersen with greater potency and easier administration, and bringing forward trials of inotersen in cardiomyopathy linked to TTR amyloidosis.
GSK isn’t giving up on Ionis’ pipeline entirely, however. The pharma group is still developing two Ionis drugs for hepatitis B virus in phase II trials.