Chemomab Therapeutics (NASDAQ:CMMB) and Scipher Medicine announced a definitive merger agreement that would combine the companies in an all-stock transaction, executives said during a conference call discussing the deal.
Upon closing, the combined company is expected to operate as Scipher Medicine Corporation and trade on Nasdaq under the ticker symbol SCIP. Dr. Reg Seeto, Scipher Medicine’s chief executive officer, is expected to lead the combined company, while Dr. Adi Mor, Chemomab’s co-founder and chief executive officer, is expected to join the combined company’s board of directors.
Deal Structure and Financing
Under the terms discussed on the call, pre-merger Chemomab stockholders are expected to own approximately 32% of the combined company, while pre-merger Scipher stockholders are expected to own approximately 68%, before giving effect to a concurrent financing that is expected to dilute both parties pro rata.
Chemomab stockholders are also expected to receive Contingent Value Rights, or CVRs, which would provide the opportunity to receive additional value if specified milestones are achieved, subject to the terms of the CVR agreement.
The transaction is supported by a committed $30 million private placement from Scipher’s existing investor syndicate. Mor identified participating investors as including Northpond Ventures, Khosla Ventures, Blue Owl Healthcare Opportunities, Neuberger Berman and others.
Mor said the financing, together with revenue from Scipher’s precision medicine business, is expected to fund the combined company through the planned readout of a Phase II trial of nebokitug in rheumatoid arthritis in the first half of 2028.
The boards of directors of both companies have unanimously approved the transaction, which is expected to close in the fourth quarter of 2026, subject to required approvals and customary closing conditions.
Focus on Nebokitug in Rheumatoid Arthritis
Chemomab developed nebokitug as a first-in-class anti-CCL24 antibody with a dual anti-inflammatory and anti-fibrotic mechanism of action. Mor said the drug has potential across inflammatory and fibrotic diseases where CCL24 biology is believed to play a significant role.
Chemomab initially focused on rare diseases and completed the Phase II SPRING trial in primary sclerosing cholangitis. Mor said that trial established clinical proof of concept and validated CCL24 as a contributor to the fibroinflammatory disease cycle. Over 48 weeks of treatment, she said nebokitug demonstrated a favorable safety profile, with no serious treatment-related adverse events, and produced improvements across relevant inflammatory and fibrotic biomarkers.
Mor said nebokitug has been administered to more than 100 patients across five clinical studies, with a consistently favorable safety profile and evidence of therapeutic activity.
Seeto said Scipher views rheumatoid arthritis as a large commercial opportunity, citing a $24 billion global market and a significant unmet need. He said about two-thirds of rheumatoid arthritis patients do not achieve low disease activity or remission with current therapies, and described the current treatment approach as relying too heavily on trial and error.
Scipher’s Precision Medicine Platform
Scipher has developed Spectra, an AI network medicine platform that integrates transcriptomic data and network biology to identify molecular treatment response signatures and support target selection in immune-mediated diseases, Seeto said.
The company also markets PrismRA, which Seeto described as the first and only CMS-approved molecular treatment response signature designed to guide targeted therapy selection in rheumatoid arthritis. He said PrismRA has been ordered by more than 1,700 rheumatologists and used in more than 45,000 patients.
According to Seeto, real-world data submitted to CMS showed that PrismRA-guided patients achieved low disease activity at twice the rate and remission at three times the rate of external controls receiving standard-of-care treatment, with statistical significance across reported outcomes.
Seeto said Scipher used its platform to evaluate clinical-stage targets predicted to have the highest efficacy response in rheumatoid arthritis. He said CCL24 emerged as the leading target and that nebokitug’s anti-CCL24 mechanism ranked in the top 1% of targets analyzed on Scipher’s clinical platform for predicted rheumatoid arthritis efficacy.
Planned Phase II Trial
The combined company plans to advance nebokitug into a Phase II trial in rheumatoid arthritis using a precision medicine strategy. Seeto said the study is designed to use PrismRA to pre-screen and identify patients who are unlikely to achieve low disease activity or remission with TNF inhibitors, which he described as the current standard of care in first-line treatment.
The planned trial is expected to enroll approximately 140 patients at global sites across two dosing cohorts and a placebo cohort. Seeto said the primary endpoint will be ACR20 at week 12, with standard secondary endpoints also included.
The companies expect to submit a pre-IND package in the second half of 2026 and, subject to regulatory feedback, dose the first patient in the first quarter of 2027. Top-line Phase II data are anticipated in the first half of 2028.
Seeto also said Scipher has identified a preliminary CCL24 biomarker response signature. After the Phase II study, the company plans to use patient samples collected during the trial to validate that signature, with the goal of supporting a companion diagnostic strategy for a Phase III program.
Mor said the opportunity remains to pursue further partnering for nebokitug in primary sclerosing cholangitis. Seeto said the combined company would have a revenue-generating rheumatoid arthritis diagnostics business, a precision medicine platform for drug development and a clinically validated anti-CCL24 antibody with therapeutic potential across multiple inflammatory and fibrotic conditions.
About Chemomab Therapeutics (NASDAQ:CMMB)
Chemomab Therapeutics (NASDAQ:CMMB) is a clinical-stage biopharmaceutical company focused on the discovery, development and commercialization of next-generation antibody therapies. The company leverages a proprietary antibody engineering platform to generate novel bi- and multi-specific antibodies with applications in oncology, infectious diseases and inflammatory disorders. By combining cutting-edge discovery tools with translational research, Chemomab aims to advance promising candidates from early proof-of-concept through clinical development.
Among its pipeline programs, Chemomab is advancing antibody candidates designed to target key tumor antigens and pathogen-specific epitopes.
