GlaxoSmithKline PLC said that a combination of its experimental drug GSK3359609 and Merck & Co. Inc.'s Keytruda helped reduce tumors in a type of head and neck cancer in certain patients who took part in an early-stage study, data presented at the European Society for Medical Oncology's 2019 scientific meeting showed.
The London-based pharmaceutical giant's GSK3359609 is designed to enhance the function of T cells, which play a central role in the immune response against diseases, by stimulating a protein known as inducible T cell costimulator, or ICOS.
New Jersey-based Merck's best-selling drug Keytruda, or pembrolizumab, works by boosting the immune system's ability to kill cancer cells by blocking healthy cells' PD-1 protein from linking up with a partner arm on the surface of cancer cells known as the PD-L1 protein.
GSK tested the experimental drug in combination with Keytruda in a phase 1 study, named Induce-1, in patients with head and neck squamous cell carcinoma — the seventh most common cancer worldwide with about 600,000 new cases diagnosed annually, according to GSK's Sept. 28 news release.
Squamous cell carcinoma is a type of cancer that arises from cells that are found in the outer layer of skin and in the mucous membranes — moist tissues that line body cavities such as the airways and intestines. Head and neck squamous cell carcinoma, or HNSCC, develops in the mucous membranes of the mouth, nose and throat.
Patients in the study had HNSCC that had returned or spread to other parts of the body and had received up to five prior lines of treatment. The patients were divided into two groups, where one cohort that had previously received PD-1/L1 therapy was only administered GSK3359609, while the other group which had not received PD-1/L1 therapy got both Keytruda and GSK3359609.
The combination treatment reduced the tumor size in eight patients, or 24%, out of the 34 evaluable patients who received both Keytruda and GSK3359609. Patients who received the drug combination lived for a median of 5.6 months without any progression in their disease.
GSK said the Induce-1 study was conducted under an agreement with Merck, and it is continuing its relationship with Merck to support the Induce-3 phase 2/3 combination trial to be started by the end of 2019.
Keytruda, which is approved in a number of countries for treating multiple types of cancer, generated global sales of about $2.63 billion in the second quarter.
The European Society for Medical Oncology is holding its 2019 scientific meeting in Barcelona, where more than 3,900 study abstracts have been submitted for review by oncology professionals from around the world.
