“Although the decision to discontinue the RIST4721 development program is disappointing for the Aristea Therapeutics team and patients in need of new treatment options, we believe it is absolutely the right decision to protect patient safety which must always be paramount in drug development,” said president and CEO James Mackay. “The Board’s decision to dissolve Aristea Therapeutics was reached after exploring a range of strategic alternatives and is a sound business decision.”

Aristea launched in December 2018 after being spun out of AstraZeneca, from which it obtained exclusive global rights to RIST4721, a solid oral investigational therapy for inhibiting CXCR2, a prominent cytokine receptor that plays a critical role in regulating neutrophils (white blood cells) to areas of inflammation.

RIST4721 was being trialed in four neutrophil-mediated autoimmune and chronic inflammatory conditions: palmoplantar pustulosis, skin condition hidradenitis suppurativa; genetic disorder familial Mediterranean fever and Behcet's disease. Aristea did not disclose specifics about the safety issues.

In July 2021, the therapy’s potential attracted $63 million in Series B financing, led by Novo Holdings and also including Pfizer unit Arena Pharmaceuticals, with which Aristea entered into a strategic collaboration. The deal gave Pfizer the exclusive option to acquire Aristea and all of its CXCR2 programs for an upfront payment of $60 million, along with a $10 million equity investment.

Author: Elaine Burridge, Freelance Journalist