It's no secret that cancer vaccines have turned in multiple late-stage failures, putting a serious damper on enthusiasm in the field. But one oncology expert believes we'll see licensed cancer vaccines in the next two to three years in immuno-oncology combo treatments.
Dr. Gerry Messerschmidt, chief medical officer of cancer-focused CRO Precision Oncology, says scientists need to solve several problems inherent to cancer vaccine development. For instance, cancers continuously grow in the body, and they wreak havoc on the immune system.
One way to overcome those challenges is by slotting cancer vaccines into combination regiments that can include up to 32 components, Dr. Messerschmidt says, each addressing different elements of the disease. Some cancer vaccines are already in testing alongside checkpoint-inhibiting immunotherapies.
So far, he said, cancer vaccine testing has been a "glass half full or half empty" scenario.
"Edison said 'I found 2,000 ways not to develop a light bulb,'" Messerschmidt said in an interview. "In a way, we have been in the middle ages, or the dark ages, of the immune system for the last couple of centuries. We have been working on instinct, guesses; on seeing some positives but never being able to harness it.
"The last 10 years, have quadrupled or higher, our knowledge about immune system."
One drawback for cancer vaccines is that they can take a long time to become effective within the body, all while cancer continuously grows, Messerschmidt said. But as a part of combo therapies, they could play a cleanup role, helping to clear out remaining cancer cells after other therapies get the disease under control, he said.
Already aware of multiple studies incorporating these principles, Messerschmidt believes "we will see cancer vaccines in the next two to three years on the market."
That prediction comes despite a troubled history for the field. Last month, Denmark's Bavarian Nordic reported a phase 3 trial failure for its prostate cancer vaccine Prostvac, news that sent the company's shares down by half. That followed other high-profile letdowns from GlaxoSmithKline and Merck KGaA in prior years.
But the trial failures obviously haven't erased optimism. After those earlier setbacks, researchers started pairing cancer vaccines with checkpoint inhibitors, spawning a trend that's now yielded dozens of combo trials. Top cancer drugmakers including Merck, Bristol-Myers Squibb, AstraZeneca and others are testing their meds in vaccine combos.