Last week’s landmark FDA approval for breast cancer identified a new cancer target, expanding the number of patients that can be treated. Mersana Therapeutics is tracking the same new targets using drugs from the same class of therapies, and the biotech is preparing for clinical trials to demonstrate whether its shift in this approach could work in other cancers.GlaxoSmithKline wants a piece of the pie, it’s $100 million paid to biotech company Start working together.
The payment, announced after the market close on Monday, is an upfront payment that gives GSK an exclusive option to license and co-develop Mersana drug XMT-2056. Exercising that option would give the pharma giant the opportunity to add another drug to its portfolio from a therapeutic class called antibody-drug conjugates (ADCs), but in a slightly different way.
ADCs have traditionally consisted of tumor-targeting antibodies linked to tumor-killing drug payloads. The goal is to provide a targeted effect that protects healthy tissue.More than a dozen such treatments have been reviewed by the FDA, most recently on Friday Approval of AstraZeneca and Daiichi Sankyo drug Enhertu expanded to include treatment of breast cancers that express low levels of protein HER2.
Cambridge, Massachusetts-based Mersana aims to take ADCs beyond the delivery of toxic drug payloads. XMT-2056 still provides targeted delivery to tumors, but its cargo instead activates the stimulator of interferon genes (STING), a pathway of the innate immune system.Other biotechnologies in development STING-activating drugs for cancer, some of which are injected into tumors as injections. Methana said in an article Investor introduction Its approach leverages the targeting ability of ADCs to elicit immune responses in tumor cells and immune cells found within tumors. This “one punch” of both is designed to provide a more effective therapeutic effect while reducing toxic effects elsewhere in the body.
In preclinical studies, Mersana reported that its drug showed potent antitumor activity in animal models that expressed high HER2 levels as well as low HER2 levels. The company said the therapy’s efficacy was enhanced when the drug was combined with other cancer drugs, including Roche’s drugs transtuzumab and pertuzumab, checkpoint blockade drugs that target the protein PD-1, and AstraZeneca and Daiichi’s The drug Enhertu. John Lepore, senior vice president of research at GSK, said in a prepared statement that XMT-2056’s “preclinical data demonstrate how it exploits the immune system by activating the STING pathway, and its differentiated mechanism of action provides additional potential for HER2 Expressing clinical benefit in cancer patients.”
While both Enhertu and XMT-2056 target HER2, Mersana’s drug is designed to target a new part of the protein. Phase 1 testing of the drug is expected to begin “immediately,” Mersana said in an investor presentation. The study will cover a range of HER2-expressing tumors. In addition to breast cancer, the study will include gastric cancer and non-small cell lung cancer.
GSK’s oncology portfolio already includes Blenrep, ADC approved by FDA two years ago For the treatment of multiple myeloma. According to Mersana Regulatory filing, the pharma giant will likely provide dose-escalation data from a Phase 1 study on the Mersana-collaborated ADC, including a survey of subgroups of breast cancer patients most likely to benefit from the treatment. If GSK chooses to exercise its option on the Mersana drug, it could potentially receive an option-exercise payment of $90 million. Achieving clinical, regulatory and commercial milestones could add $1.27 billion to Mersana.
GSK is the biotech’s second Mersana partner signed this year. In February, the company announced a partnership with Johnson & Johnson’s Janssen biotech subsidiary.according to terms of the transaction, Mersana will use Janssen-supplied antibodies against three unspecified targets. Janssen paid Mersana $40 million up front. Mersana could receive up to $1 billion in milestone payments.
Photo by GlaxoSmithKline
