Allakos Inc. has announced the discontinuation of its AK006 development program for chronic spontaneous urticaria (CSU) following disappointing topline results from its Phase 1 clinical trial. The company will also undergo a significant restructuring, including a 75% workforce reduction.
The Phase 1 trial (NCT06072157) enrolled 34 adult patients with moderate-to-severe CSU who were refractory to antihistamines, with or without prior omalizumab exposure. Participants were randomized 2:1 to receive either 720 mg of intravenous AK006 (n=23) or placebo (n=11) every four weeks. The primary endpoint was safety and tolerability, with therapeutic activity assessed using the Urticaria Activity Score (UAS)-7 at 14 weeks.
Lack of Clinical Benefit
According to Allakos, AK006 did not demonstrate therapeutic activity in CSU patients. Exploratory efficacy results showed that the AK006 group had a mean change in UAS7 of -8.2 from a baseline of 34.4, while the placebo group had a mean change of -12.4 from a baseline of 30.5. Complete responses (UAS7=0) were observed in 9% of patients in both the AK006 and placebo arms.
"While AK006 was well tolerated, we are disappointed that the preclinical inhibitory effects observed did not translate to clinical benefit in patients with CSU," said Chin Lee, M.D, M.P.H., Chief Medical Officer of Allakos. "As a result, the Company has decided to discontinue further clinical development of AK006."
Restructuring and Financial Impact
Allakos plans to discontinue all AK006-related activities across clinical, manufacturing, research, and administrative functions. The company will retain approximately 15 employees to explore strategic alternatives, maintain regulatory and financial reporting compliance, and wind down the Phase 1 trial.
The company estimates that restructuring activities will cost between $34 million and $38 million, primarily paid out in the first and second quarters of 2025. Allakos anticipates having cash, cash equivalents, and investments in the range of $35 million to $40 million by June 30, 2025.
Previous Setbacks and Market Context
This is not Allakos' first setback in the CSU space. In January 2024, the company halted development of lirentelimab after it failed in two Phase II studies for atopic dermatitis and CSU. Following that failure, Allakos cut its workforce by 50%.
While Allakos exits the CSU drug development arena, other companies continue to advance therapies. Novartis, for instance, is progressing its CSU candidate remibrutinib through regulatory submissions following positive Phase III data. GlobalData projects remibrutinib to generate $1.2 billion in sales by 2030.
