fbpx Recurrent Glioblastoma - Plus Therapeutics (PSTV)
Recurrent Glioblastoma

The most common, complex and aggressive primary brain cancer in adults.

Recurrent glioblastoma (GBM) is a fatal, treatment-resistant, malignant brain tumor that causes numerous neurological complications, such as seizures, headaches, and vision problems.



cases diagnosed each year in the U.S.



patients succumb each year in the U.S.

What is Glioblastoma?

Current Treatment Approaches

Since the discovery of GBM in the 1920s, the U.S. FDA has only approved 4 different drugs and 1 medical device. To date, radiation is one of the few treatment approaches that has truly prolonged the life of patients with GBM, but only for a short amount of time. External beam radiation therapy (EBRT) delivers photons or x-rays that pass directly through normal brain tissue, leading to both high toxicity and residual cancer cells that regrow in roughly 1-4 months.

There is no clear standard of care in the recurrent setting.

The infiltrative nature of GBM makes it difficult to eliminate microscopic disease despite macroscopic gross-total resection, with 90% of patients having recurrence at or near the original tumor location. In the recurrent and progressive setting there are no FDA-approved treatments that significant extend a patient’s life.


of patients have
recurrence at the original
tumor location

10 mo.

On average, patients
survive 10 months
after recurrence.

One of the main treatment challenges is the location of the tumor, where only small or lipophilic molecules are able to cross the blood-brain barrier to reach the tumor. This has proven to make drug delivery very difficult. In addition, GBM cells tend to be resistant to most cytotoxic agents and even if initially sensitive, quickly develop resistance.

The Opportunity

To develop a treatment that can bypass the blood-brain barrier, increase the therapeutic window while sparing healthy brain tissue, and decrease overall toxicity.

Our lead drug candidate, rhenium (186Re) obisbemeda, is a novel radiotherapeutic with the potential to be a safe, effective and convenient radiation treatment for patients with GBM. Through Convection Enhanced Delivery (CED), rhenium (186Re) obisbemeda is infused into or adjacent to a tumor, increasing the precision and accuracy of drug delivery while reducing radiation exposure to healthy cells.

As opposed to EBRT, which requires small dose radiation treatment 5 days per week for 5-8 weeks, rhenium (186Re) obisbemeda can be administered during a single surgical procedure and a 3-4 day hospital visit.

In our ongoing ReSPECT-GBM clinical trial, supported by the U.S. NIH / NCI, we administered up to 15-20x greater dosing than what’s possible with EBRT without significant toxicity.