Alnylam stock's hot streak cooled Friday as one expert argued the company will have to run a second final-phase study of its cardiomyopathy drug to gain commercial traction.
Alnylam Pharmaceuticals tested its drug, patisiran, in patients with transthyretin-mediated amyloidosis with cardiomyopathy. In this disorder, abnormal protein called amyloid builds up on the heart, causing systemic problems.
An academic cardiologist, cited by RBC Capital Markets analyst Luca Issi, said Alnylam would need to run a second final-phase study of patisiran to secure commercial update in patients. That's because there's already a drug on the market, Vyndaqel from Pfizer.
Alnylam's data unveiled Wednesday were "clearly positive, but not a slam dunk," he said. After a year of treatment, patisiran recipients could walk farther for six minutes. They also reported improved quality of life in a questionnaire. The results sent Alnylam stock flying 49% in a day.
The doctor "thinks there is a 75% chance that the FDA approves patisiran on (this study) given the drug is safe and it did hit the primary (goal)," Issi said in a report to clients. "However, on commercial adoption, he is cautious given he would not put any new patient on it, nor switch any (Vyndaqel) patient."
Alnylam Stock Breaks Out
On today's stock market, Alnylam stock sank 2.4% to 218.58. After soaring more than 49% on Wednesday, Alnylam tacked on another 5.7% on Thursday. Shares broke out of a consolidation with a buy point at 212.10, according to MarketSmith.com.
The doctor thinks there's a chance the improvement in six-minute walking distance is likely modest. Further, there are benefits to Vyndaqel. Pfizer offers an oral medication, while Alnylam's drug comes via intravenous infusion.
Vyndaqel also won approval based on its ability to improve survival in patients and lower the number of hospitalizations due to heart problems — a different standard from the six-minute walking test. But the drug is also expensive, costing $115,000 per year. Patisiran, on the other hand, gained approval for polyneuropathy patients and requires no copay for Medicare Part B coverage. Polyneuropathy is the nerve component of the same amyloid-building disease.
Still, RBC's Issi kept his outperform rating on Alnylam stock. He noted Alnylam won't have the results of its next patisiran study in cardiomyopathy until 2024.
Intellia Faces A Setback
Also pressuring Alnylam stock, on Thursday, Intellia Therapeutics said it would back off the high dose in its cardiomyopathy study. The same high dose in a polyneuropathy patient led to an asymptomatic incident of heightened liver enzymes. Intellia stock tumbled 8.7% in response.
The two companies have different approaches to the same disease. Alnylam's drug silences the gene responsible for making the aberrant protein. Intellia is taking a gene-editing approach.
Follow Allison Gatlin on Twitter at @IBD_AGatlin.
