Radiance Biopharma is heating up the ROR1 race. The U.S. biotech is paying (PDF) China’s CSPC Megalith Biopharmaceutical $15 million upfront for rights to an antibody-drug conjugate (ADC), securing itself a shot at challenging Merck & Co. for the opportunity.
Merck is setting the pace in the ROR1 race. In December, the Big Pharma reported a 100% complete response rate in a trial of its ROR1-directed ADC. The data emboldened Merck to take the candidate, which it acquired in the $2.75 billion VelosBio buyout, into phase 3. Boehringer Ingelheim dropped out in 2020 but companies including CStone Pharmaceuticals, Immunome and Ipsen are still giving chase.
Radiance has secured a spot in the chasing pack by paying Megalith $15 million upfront for exclusive rights to SYS6005 in markets including the U.S. and European Union. Megalith, a subsidiary of CSPC Pharmaceutical, is in line to receive up to $150 million in development and regulatory milestones. If the ADC comes to market, sales milestones could add more than $1 billion to the total value of the deal.
CSPC secured (PDF) Chinese regulatory clearance to start a clinical trial of the ADC in December. The company sees SYS6005 as a potential treatment for blood cancers, ovarian cancer and non-small cell lung cancer. Merck reported the 100% complete response rate in diffuse large B-cell lymphoma (DLBCL) and has moved into phase 3 in that setting.
The Big Pharma terminated a solid tumor study last year, citing business reasons, but is still running a phase 1/2 bladder cancer trial. Merck is also testing its ADC candidate in blood cancers beyond DLBCL. Immunome’s phase 1 trial, which started this month, is assessing a ROR1 ADC in advanced B-cell lymphomas and solid tumors. CStone, which entered the clinic in 2022, is going after similar indications.
Immunome paid Zentalis $35 million in cash and stock for global rights to the then-preclinical ADC last year. Ipsen agreed to pay Sutro Biopharma $90 million in the near term for global rights to a preclinical ADC months after the Immunome deal. CStone became an early entrant to the ROR1 race when it paid LigaChem Biosciences $10 million upfront for global rights to LCB71 in 2020.