Roche’s Acquisition of Spark Falls Short as Another Therapy Exits Pipeline

Roche’s 2019 acquisition of Philadelphia-based gene therapy specialist Spark Therapeutics for over $4 billion is proving disappointing, as the company has discontinued another acquired therapy. Dirloctocogene samoparvovec, also known as SPK-8011, an experimental hemophilia A gene therapy, has been dropped from Roche’s pipeline for what the company describes as “strategic reasons.”
Even before its termination, SPK-8011 was a financial burden. Last year, Roche wrote down $606 million in losses after revising sales projections for the therapy. This substantial loss underscored the monetary challenges posed by the personalized medicine candidate.
The decision to halt development followed the withdrawal of the KEYSTONE 1 phase 3 study from ClinicalTrials.gov, the U.S. clinical trial registry. Although KEYSTONE 1 was announced in March, no patients had been enrolled before its termination.

Roche’s decision aligns with its strategic focus on advancing a new candidate for hemophilia A: an enhanced function factor VIII (FVIII) therapy. However, as of late October, the new program has yet to appear in Roche’s online pipeline, where SPK-8011 is still listed.
A Roche spokesperson expressed optimism about the new FVIII candidate, stating:
“This decision is based on our belief that an enhanced function FVIII variant has the potential to address remaining unmet needs and reduce the treatment burden for patients. It builds on the promising results seen in the phase 1/2 dirloctocogene samoparvovec study, which assessed the safety and efficacy of factor VIII gene transfer in individuals with hemophilia A, demonstrating favorable safety, durability, and predictability using a low-dose approach.”
SPK-8011 isn’t the first Spark program Roche has had to abandon. In July, the company dropped Spark’s Pompe disease gene therapy candidate SPK-3006, citing a “strategic portfolio prioritization.” The decision reflects the intense competition in the gene therapy market for Pompe disease, where multiple companies are advancing potential solutions alongside the already established standard of care.
Previously, in 2022, Roche eliminated SPK-8016 (also known as RG6358) from its pipeline. This hemophilia A gene therapy candidate, designed for up to 30% of individuals with severe or moderately severe hemophilia A who develop inhibitors to FVIII, was in early development when it was discontinued.
To strengthen its position in personalized medicine following these setbacks, Roche recently signed a billion-dollar agreement with Dyno Therapeutics. This deal provides Roche with access to Dyno’s innovative gene therapy technologies, including artificial intelligence-driven design and high-throughput in vivo data for neurological disease treatments.
Roche’s latest partnership builds on its 2020 collaboration with Dyno. The company will develop advanced delivery tools using novel adeno-associated virus (AAV) vectors with improved functional properties, supporting Roche’s gene therapy ambitions.