Glioblastoma (GBM) is the most common and aggressive brain cancer in adults. Even after surgery, radiation, and chemotherapy, the tumor almost always returns. When GBM recurs, treatment options are very limited and usually provide only short-term benefit. There is a strong need for new and more effective therapies for patients with recurrent GBM.

Many GBM tumors show changes in a protein called EGFR, which helps cancer cells grow. Cetuximab is a medicine that targets EGFR and blocks its activity. It is already used for other cancers, and research suggests it may help slow tumor growth in GBM, especially in tumors with EGFR amplification or EGFRvIII mutation. Lomustine (also known as CCNU) is an oral chemotherapy commonly used for recurrent GBM. Although it offers modest benefit when used alone, it is known to work better in combination with other treatments.

The CLARITY-GBM study is a Phase 2 clinical trial that will test whether giving cetuximab along with lomustine can better control tumor growth in adults whose GBM has returned after standard treatment. About 25 participants will take part across multiple hospitals. All participants will receive cetuximab through a vein every two weeks and lomustine as a single oral dose every six weeks.

The main goal is to find out how many patients remain alive and without tumor progression six months after starting treatment. The study also aims to evaluate overall survival, MRI-based tumor response, quality of life, side effects, and steroid use. Blood and tumor samples may also be collected to explore biomarkers that could help predict treatment response.

This research aims to determine whether the combination of cetuximab and lomustine can offer a promising new treatment option for people with recurrent glioblastoma.