With limited mesothelioma treatment options available, the results from AstraZeneca’s DETERMINE trial were highly anticipated, and not just by those in the mesothelioma community, but the entire medical community at large. The drug, tremelimumab, was originally granted an orphan drug designation for malignant mesothelioma, but the big question was: Would it extend the overall survival rates of patients?

With average survival rates for victims of malignant mesothelioma normally averaging around 1 year after formal diagnosis, researchers have been looking for drug that would work to extend the low survival rate for patients with this rare and deadly cancer.

Unfortunately, this week, AstraZeneca announced that the highly anticipated drug had proven unsuccessful in its clinical trials. 

The Basics of AstraZeneca’s DETERMINE Tremelimumab Study

In order to fully understand any results, it’s important to know the details of what was being studied. AstraZeneca’s double-blind, placebo-controlled, phase IIb DETERMINE trial enrolled 571 participants with unresectable pleural or peritoneal malignant mesothelioma. In order to qualify for the study, the participants had to have had prior attempts with other mesothelioma treatments – such as chemotherapy – which were unsuccessful. They also couldn’t qualify as candidates for surgery. With a new case rate of around 3,200 per year, that makes for a very small amount of eligible participants.

In a 2:1 ration, patients were given tremelimumab or a placebo. While the study did not yet publish data from the trial, they did release that the primary objective, increasing the overall survival rate, has failed its parameters.

The bottom line: For patients with challenging-to-treat mesothelioma cases, the goal of improving overall survival with tremelimumab alone was unsuccessful.

A Setback for AstraZeneca and the Mesothelioma Community

This news comes as a major setback for AstraZeneca, and its stock value (AZN) fell over 2.2% following the announcement. With positive results, this drug could have boosted the company in the ever-competitive cancer-drug market. Current frontrunners to watch out for are Merck & Co., Bristol-Myers Squibb Co., and Roche Holding Ltd.

Unfortunately, this news also comes as an even bigger setback to the mesothelioma-medical community. Since most mesothelioma diagnoses are in the late stages, treatment options are quite limited. With a diagnosis of stage 3 mesothelioma, surgery may or may not be an option, and treatments, such as chemotherapy or radiation, are discussed on a case-by-case basis. A stage 4 diagnosis is usually treated with palliative care.

A successful study would have brought much-needed hope to the mesothelioma community – especially for those who have been diagnosed with stage 3 or stage 4 cancer.

But Don’t Give Up on Tremelimumab Just Yet

Though AstraZeneca’s tremelimumab has failed to work as a monotherapy for mesothelioma, it doesn’t rule it out as an effective treatment option that can be used in combination with other forms of treatment.

In fact, just a few weeks ago, AstraZeneca triumphantly announced a successful study of the combination of their drugs: durvalumab and tremelimumab. In a small proof-of-concept study, the combination treatment indicated a 23 percent tumor-response rate in non-small cell lung cancer.

Robert Iannone, AstraZeneca’s head of immune-oncology stated:

“We are disappointed that tremelimumab monotherapy did not demonstrate a survival benefit in this patient population with no approved medicines beyond first-line treatment. However, we remain confident in tremelimumab’s clinical activity in combination, as shown in our recently published Study 006 trial of tremelimumab and durvalumab…”

It’s not time to give up hope that the medical community will find a safe, effective treatment for end-stage, difficult-to-treat cancers like mesothelioma.

AstraZeneca remains hopeful:

“By harnessing the power of four scientific platforms – immuno-oncology, the genetic drivers of cancer and resistance, DNA damage repair, and antibody drug conjugates – and by championing the development of personalized combinations, AstraZeneca has the vision to redefine cancer treatment and one day eliminate cancer as a cause of death.”