Spero Therapeutics Reports Q3 2026 Results, Announces $105M Financing and SP001 In-Licensing

Spero Therapeutics, Inc. (Nasdaq: SPRO) reported its financial results for the third quarter ended September 30, 2026, and provided an update on its business operations. The company announced that it has secured a $105 million non-recourse, non-dilutive milestone and royalty financing with affiliates of HealthCare Royalty Partners (HCRx), a business of KKR. This transaction was closed in July 2026 in exchange for a portion of anticipated payments owed to Spero by GSK under the Utebzi agreement. Spero retains a 35% interest in any remaining GSK payments after the required note payments to HCRx are satisfied.

In July 2026, Spero also in-licensed SP001 from affiliates of Innovent Biologics, Inc. The agreement grants Spero exclusive worldwide rights, excluding Greater China, to research, develop, manufacture, and commercialize the antibody. Spero paid a $35 million upfront payment for these rights. SP001 is a third-generation, fully humanized, Fc-silent IgG1 monoclonal antibody targeting CD40L. Innovent previously completed Phase 1 studies in healthy volunteers and patients with primary Sjögren’s disease. Spero plans to initiate a Phase 2 study for SP001 in IgG4-related disease (IgG4-RD) in the second quarter of 2027.

Regarding financial performance, Spero reported a net loss of $44.3 million for the third quarter of 2026, compared to a net loss of $7.4 million in the prior year. Research and development expenses for the quarter were $38.2 million, a significant increase driven by the $35 million upfront payment for the Innovent licensing agreement. General and administrative expenses decreased to $3.7 million from $4.2 million in the prior year. As of September 30, 2026, the company held $107.9 million in cash and cash equivalents. Spero expects this cash balance to be sufficient to fund operations into the second half of 2029.

The company also announced personnel changes, including the appointment of Debra Jeske Zack, M.D., Ph.D., as Chief Medical Officer, and Amy Rock, Ph.D., as Chief Regulatory and Quality Officer. Additionally, William Ho, M.D., Ph.D., was appointed to the Board of Directors and Development Committee, effective November 10, 2026.