Challenges of Treating Brain Tumors
Brain tumors are winning
More than 138,000 U.S. patients and 1.4 million patients worldwide are struggling with malignant brain tumors. By the end of the year, another 256,000 will be diagnosed. For the most common malignant brain tumor – glioblastoma multiforme (GBM) – nine out of ten will lose their battle with the disease within five years. The average five-year survival rate of patients with GBM is less than 5% and has shown no notable improvement in the last three decades.
Survival rate of patients with GBM has not improved in the last 30 years.
An unfulfilled promise for new drugs
Despite these staggering statistics, there has been very little progress in drug development for brain tumor patients. Between 1998 and 2014, 78 investigational brain tumor drugs were evaluated in advanced clinical trials, but only three gained FDA approval. Of these, temozolomide (TMZ), an oral chemotherapy, has been the only one to show a survival benefit.
The current standard of care for patients with newly-diagnosed glioblastoma has limited effectiveness and a second line has not been established.
The lack of new treatments for aggressive brain tumors requires a bold approach to rapidly identify new, effective therapies that will increase life expectancy and contribute to a cure.
WHY HAS DRUG DEVELOPMENT LAGGED FOR BRAIN CANCER?
YOUR BRAIN IS DESIGNED TO KEEP DRUGS OUT
The brain is equipped with a protective mechanism called the blood-brain barrier (BBB). Its function is to prevent harmful substances from entering the central nervous system. Unfortunately, this also means that most new drugs can’t get through and treat the brain tumor. The BBB is one of the most critical obstacles researchers face in developing new effective therapies for patients with malignant brain tumors. Our phase 0 clinical trial approach is uniquely designed to rapidly identify which drugs can and cannot effectively penetrate the BBB.
EACH PATIENT’S BRAIN TUMOR IS DIFFERENT FROM ANOTHER
Unlike other cancers such as breast or lung, brain tumors are extremely genetically heterogeneous. This means each brain tumor is slightly different from another. A single patient’s tumor can even consist of many different unique cell types and when the tumor returns after surgery, the genetics will have completely transformed. This heterogeneity is not something that can be easily modeled in a laboratory to reliably give us an indication for what is going to happen in the human disease. For this reason, a single drug is highly unlikely to be effective. Our strategy is to identify agents that tackle the roadblock of the blood-brain barrier and build upon those agents in drug combinations.
SMALL PATIENT POPULATION
In addition to the complexities mentioned above, malignant brain cancers like glioblastoma are not as prevalent as other cancer types, which limits the resource and industry interest from biopharmaceutical companies. Decades of data reveal market size is the strongest predictor of new drug discovery.
