Alnylam receives Portuguese, Swedish, British approvals to initiate ALN-TTR01 Phase I study in ATTR

Alnylam Pharmaceuticals, Inc. (Nasdaq: ALNY), a leading RNAi therapeutics company, announced today that its applications for ALN-TTR01 have been given clearance by Portuguese, Swedish, and British regulatory authorities to begin clinical testing. The trial will begin enrolling patients shortly in a blinded, randomized, placebo-controlled, multicenter Phase I study. ALN-TTR01 is a systemically delivered RNAi therapeutic being developed for the treatment of transthyretin (TTR)-mediated amyloidosis (ATTR), including familial amyloidotic polyneuropathy (FAP) and familial amyloidotic cardiomyopathy (FAC).

“a major scientific breakthrough that happens once every decade or so”

ATTR is caused by mutations in the TTR gene, which is expressed predominantly in the liver, that result in the accumulation of pathogenic deposits of mutant and wild-type TTR protein in multiple extra-hepatic tissues, including the peripheral nervous system, heart, and the gastrointestinal tract. Pre-clinical studies in a mouse transgenic model have shown that treatment with ALN-TTR01 results in regression of pre-existing pathogenic TTR deposits in peripheral tissues including dorsal root ganglia, sciatic nerve, stomach, and intestines. Further, ALN-TTR01 administration in non-human primates was found to result in dose-dependent and durable, yet reversible silencing of the TTR gene and plasma levels of TTR.

"We are very excited with our ALN-TTR program, as it holds significant promise as a potential breakthrough therapy for this devastating disease," said Akshay Vaishnaw, M.D., Ph.D., Senior Vice President, Clinical Research at Alnylam. "Having now received approvals for initiation of our Phase I study, we look forward to the next stage of clinical translation in this program with dosing starting in the next few weeks. In particular, we aim to demonstrate safety and tolerability as the study's primary objective. Further, since we can measure plasma levels of TTR in patient plasma samples, we expect to have an opportunity to assess preliminary human proof of concept in this study."

The Phase I trial will be conducted in Portugal, Sweden, and the U.K., and is a randomized, blinded, placebo-controlled dose escalation study designed to enroll approximately 28 patients with ATTR. The primary objective is to evaluate the safety and tolerability of a single dose of intravenous ALN-TTR01, with patients being enrolled into five sequential cohorts of increasing doses of ALN-TTR01 ranging from 0.01 to 0.4 mg/kg. Secondary objectives include characterization of plasma and urine pharmacokinetics of ALN-TTR01 and assessment of pharmacodynamic activity based on measurements of circulating TTR plasma levels.

ALN-TTR01 is being advanced to clinical development using stable nucleic acid-lipid particles (SNALP) delivery technology developed in collaboration with Tekmira Pharmaceuticals Corporation.