Pfizer hedges bets on gene therapy deal

Pfizer has stopped short of joining 2019's gene therapy buying spree, instead acquiring a 15% of Vivet Therapeutics, and securing an option to buy at a later date.

Recent weeks has seen some major M&A deals in the gene therapy space, with pharma now seeing it as an integral part of the sector’s future: Roche acquired Spark Therapeutics last month for $4.3bn while earlier this month Biogen snapped up Nightstar Therapeutics for $800m.

Pfizer will pay €45m ($51m) upfront to the Paris-based gene therapy company, plus up to €560m ($635.8m), subject to certain clinical, regulatory, and commercial milestones.

In this way, the US pharma company is sidestepping the kind of bidding war that drove up the price of Spark Therapeutics – something which it clearly wants to avoid, as the business model for cell and gene therapies is still being established.

Pfizer had looked like the most obvious buyer for Spark, as the two companies are co-developing a gene therapy treatment for haemophilia B. It’s likely that Pfizer was part of the bidding war for Spark (detailed in its recent filing), though the identity of the other interested parties have not been disclosed.

Vivet Therapeutics’ lead candidate is VTX-801, a gene therapy for Wilson disease, a devastating rare, chronic, and potentially life-threatening liver disorder. The disease is also being targeted by Alexion with its oral treatment WTX101 in phase 3 trials.

Vivet's candidate is only now entering clinical trials, and has to prove its efficacy in an increasingly crowded gene therapy field, but will aim to provide an outright cure for the condition.

Pfizer will work closely with Vivet to help it develop its expertise in liver-directed AAV gene therapy for Wilson disease and other metabolic conditions.

Pfizer's rare disease leader Seng Cheng

“VTX-801 could provide a potentially transformative therapeutic option for patients with Wilson disease by directly addressing the underlying cause of the disease—the inability to excrete copper owing to a mutation in the gene that codes for that function,” said Seng Cheng, senior vice president and chief scientific officer of Pfizer’s rare disease research unit.

Pfizer can exercise its option to acquire 100% of Vivet following the company’s delivery of certain data from the phase 1/2 clinical trial for VTX-801. As part of the transaction, Pfizer senior executive Monika Vnuk, M.D., vice president, Worldwide Business Development, will join Vivet’s board. Other terms of the transaction were not disclosed.

Vivet co-founder and chief scientific officer Gloria Gonzalez-Aseguinolaza said: “The potential of VTX-801 has already been demonstrated in preclinical models and our partnership with Pfizer will help accelerate development of VTX-801 and expand our other innovative technologies.”