Tempered excitement
In a comment, Ronald Witteles, MD, professor of cardiovascular medicine, Stanford (Calif.) University, and founder/codirector of the Stanford Amyloid Center, said that “antibody-based amyloid removal strategies are not currently clinically available and represent a fundamentally different mechanism to treat the disease from what we currently have.
“While the data are encouraging and will generate excitement for later-phase studies, we’re talking about small numbers of patients and nothing definitive should be drawn from this data,” said Dr. Witteles, deputy editor of JACC: CardioOncology.
“The biggest caveat is that similar approaches of antibody removal of amyloid deposits for other forms of amyloidosis — most notably AL amyloidosis (amyloid light chain or primary amyloidosis) – have failed in late-phase trials. Although there is reason to believe that ATTR amyloidosis may be more amenable to improvements with amyloid fibril removal than AL amyloidosis, the unimpressive results in other forms of amyloidosis still do temper the excitement to a degree.”
Like Dr. Garcia-Pavia, Dr. Witteles said, “Ultimately, we are going to need to see a phase 3 clinical trial which shows that NI006 – on top of standard-of-care treatment – improves hard outcomes in the disease. As treatment options likely expand in the coming years, that is likely to be a harder and harder bar to reach.”
Furthermore, although the safety profile was favorable overall, it “wasn’t entirely clean,” given cytokine release syndrome in three patients, a lowering of platelet counts in a couple of patients, and musculoskeletal side effects that triggered two to withdraw from the study. “Unless that changes,” he said, “that will be a barrier for some patients.”
Overall, he noted, “With the vast majority of patients being able to be diagnosed noninvasively, and with treatment options now available, we have seen a true explosion in the number of patients being diagnosed.
“But we also know that the large majority ... are still not getting diagnosed or are having huge delays in diagnosis. As such, the biggest thing we can do for patients with the disease is to continue to educate people about it,” Dr. Witteles concluded.
The study was funded by Neurimmune. Dr. Garcia-Pavia disclosed ties to Alexion, Alnylam Pharmaceuticals, AstraZeneca, Attralus, BridgeBio, General Electric, Intellia, Ionis Pharmaceuticals, Neurimmune, Novo Nordisk, and Pfizer. Dr. Witteles reported ties to Alexion, Alnylam, AstraZeneca, BridgeBio, Intellia, Ionis, Janssen, Novo Nordisk, and Pfizer.
A version of this article first appeared on Medscape.com.