The first ever RNA interference (RNAi) drug, used to treat polyneuropathy in patients with hereditary transthyretin-mediated amyloidosis, has been given marketing approval by the European Commision.
The approval follows that of the US FDA who gave the green light to US biotech Alnylam Pharmaceutical’s Onpattro (patisiran) earlier this month following positive Phase III findings in 2017.
“The approval of Onpattro marks the beginning of RNAi therapeutics as a whole new class of medicines coming to the market. These medicines have transformative potential for a wide range of diseases including rare diseases as well as more common diseases,” Theresa Heggie, Head of Europe at Alnylam, told me.
“We are ready to launch patisiran and hope it will help to meet the pressing need for new treatment options for patients living with hereditary transthyretin-mediated amyloidosis in Europe.”
RNAi drugs work by interfering with the production of malfunctioning proteins by faulty genes. Small interfering (si) RNA’s are created that can effectively ‘silence’ the problem genes.
The full Phase III results from Alnylam’s trial were published in July. Out of 225 patients with the condition, two-thirds received an injection of the therapy once every 3 weeks and the third received a placebo injection. Statistically significant improvements in neuropathy symptoms, quality of life, walking speed and BMI were seen in patients treated with Onpattro versus those given placebo.
Alnylam had a 2014 partnership deal with Sanofi to develop both patisiran and fitusiran, an RNAi treatment for hemophilia A and B. Originally, Alnylam would have kept commercialization rights to both drugs in North America and Western Europe, with Sanofi targeting the rest of the world.
However, with approval for patisiran on the horizon, the two companies restructured the deal in January this year and Alnylam now has global rights to patisiran in return for giving up the global rights to fitusiran to Sanofi.
While it has shown good results in clinical trials, fitusiran had a setback in September 2017 when a patient enrolled in its Phase II trial died. All trials were halted temporarily, but the FDA gave the green light to continue testing in January and recruitment for Phase III is ongoing.
In 2006, the Nobel Prize in Physiology or Medicine was awarded jointly to Andrew Fire and Craig Mello for discovering RNA interference. However, effective and safe therapies have been a long time in the making. Many companies, including Roche, Merck, and Abbott previously canceled their programs. An earlier hereditary transthyretin-mediated amyloidosis candidate from Alnylam — revusiran — also had to be canceled in 2016 after 18 patients died during a Phase III trial.
“Rather than thinking about it in terms of success or failure, we tend to think about it in terms of commitment and belief in RNAi – a belief that we continued to demonstrate when others gave up,” emphasized Heggie.
It looks like the US firm has finally cracked the RNAi puzzle, but it remains to be seen how the drug will perform long term and how other candidates will fare now Alnylam has opened the gates for other players in this space.
Images via Alnylam