Neurotrope Alzheimer's drug data fails to impress; shares plunge

Neurotrope Inc said on Monday the smaller dose of its experimental Alzheimer's drug met the main goal in a small mid-stage study, but shares tumbled 31 percent in premarket trading as investors were not impressed with the data.

In the Neurotrope trial, two doses of Bryostatin-1 were tested against a placebo, in addition to the standard treatment, in 147 patients with moderate-to-severe disease. A total of 113 patients completed the study.

Among those, 80 patients on the smaller 20 microgram (mcg) dose of the drug achieved a statistically significant improvement in cognition on a scale used to measure severe dementia, the company said.

However, in about 90 patients who received the same dose but did not complete the study, Bryostatin-1 did not bring about a statistically significant improvement, the company added.

Neurotrope, which did not provide details about the performance of the higher 40 mcg dose, said a higher incidence of diarrhea was seen with the smaller dose.

The drug, which comes from a marine source, is designed to address an underlying cause of the disease by inducing growth of synapses in the brain and prevent cell death.

Bryostatin-1 was originally evaluated as a treatment for cancer. Following its failure as an oncology treatment, Neurotrope inked a deal to supply the expensive compound to National Cancer Institute (NCI).

Neurotrope, which has now found a way to synthetically develop the drug, hopes to discuss a path forward with the U.S. health regulator, it said on Monday.

The announcement comes months after Merck & Co Inc said it would halt a late-stage trial of its Alzheimer's drug, verubecestat, after determining that it had no chance of working.

Verubecestat belongs to a class of experimental drugs that target an enzyme involved in the formation of the toxic amyloid protein that turns into plaques in the brains of Alzheimer’s patients.

Several companies are pinning hopes on this mechanism, including Eli Lilly & Co, Biogen as well as Novartis in collaboration with Amgen.

Existing treatments only lessen symptoms or slow disease progression, and developers have suffered crushing disappointments in their efforts to find an effective way to reverse cognitive decline that affects more than 5 million Americans with Alzheimer's.

Researchers are now increasingly focusing on attacking the disease before symptoms take hold. Analysts say any treatment that successfully interferes with the underlying cause of the disease would be virtually guaranteed multi-billion dollars in sales.

The company's shares were down at $13 before the bell on Monday.