Myo­statin in­hibitors — en­gi­neered to build mus­cle and im­prove mo­bil­i­ty in pa­tients — the­o­ret­i­cal­ly make sense for use in pa­tients with mus­cle-wast­ing dis­eases. But the field is lit­tered with fail­ure — and so it was hard­ly sur­pris­ing when Ac­celeron, which years ago scrapped a myo­statin pro­gram it had part­nered with Shire, dis­closed an­oth­er flopped myo­statin drug on Mon­day.

Ac­celeron’s drug, ACE-083, was be­ing test­ed in a mid-stage study in pa­tients with Char­cot-Marie-Tooth dis­ease (CMT), a group of in­her­it­ed dis­or­ders that cause nerve dam­age and are char­ac­ter­ized by small­er, weak­er mus­cles.

In the study, ACE-083 in­duced a sta­tis­ti­cal­ly sig­nif­i­cant in­crease in mean to­tal mus­cle vol­ume — meet­ing the main goal. How­ev­er, that in­crease did not trans­late to sta­tis­ti­cal­ly sig­nif­i­cant im­prove­ments in any of the func­tion­al or qual­i­ty of life sec­ondary end­points, ver­sus place­bo. Ac­celeron is, there­fore, dis­con­tin­u­ing the de­vel­op­ment of the ex­per­i­men­tal com­pound, it said.

Back in Sep­tem­ber, ACE-083 failed to elic­it func­tion­al ben­e­fit in a sep­a­rate study in pa­tients with fa­cioscapu­lo­humer­al mus­cu­lar dy­s­tro­phy, a ge­net­ic mus­cle-wast­ing con­di­tion that caus­es the mus­cles of the limbs, shoul­ders, and face to weak­en.

This CMT re­sult was not sur­pris­ing, giv­en the sim­i­lar lack of func­tion­al ben­e­fit from the FSHD tri­al, SVB Leerink’s Ge­of­frey Porges wrote in a note.

The Cam­bridge, Mass­a­chu­setts-based com­pa­ny’s stock $XL­RN closed down about 6.6% at $85.29 on Mon­day and was bare­ly down 0.1% in Tues­day pre­mar­ket trad­ing.

ACE-083 is the lat­est ca­su­al­ty in a list of myo­statin ef­forts that have crashed and burned. Ac­celeron and Shire halt­ed clin­i­cal work on ACE-031 as ear­ly as 2011 and scrapped the pro­gram al­to­geth­er in 2013; No­var­tis’ bima­grum­ab failed a mid-stage study in 2016; Pfiz­er dropped the Duchenne plans for do­ma­grozum­ab fol­low­ing a dis­ap­point­ing Phase II tri­al in 2018; and last No­vem­ber, Roche aban­doned its Duchenne drug (ac­quired from Bris­tol My­ers Squibb in 2017) af­ter a fu­til­i­ty analy­sis sug­gest­ed de­vel­op­ing the com­pound fur­ther was fu­tile.

Myo­statin is a pro­tein that forms part of the trans­form­ing growth fac­tor be­ta (TGFβ) su­per­fam­i­ly — a group of pro­teins that help con­trol the growth and de­vel­op­ment of tis­sues across the body. The pro­tein nor­mal­ly re­strains mus­cle growth, en­sur­ing that mus­cles do not grow too large.

Mean­while, Ac­celeron has oth­er ar­eas of fo­cus.

The com­pa­ny in No­vem­ber se­cured the ap­proval of Cel­gene-part­nered red blood cell boost­ing drug Re­blozyl — known chem­i­cal­ly as lus­pa­ter­cept — to treat ane­mia in pa­tients with be­ta-tha­lassemia who re­quire reg­u­lar trans­fu­sions. Al­though its use in myelodys­plas­tic syn­dromes — which will like­ly de­ter­mine if the drug, pegged to even­tu­al­ly gen­er­ate glob­al peak sales of more than $3 bil­lion, is a big com­mer­cial suc­cess  — is still un­der Phase III re­view.

Ear­li­er this year, fo­cus al­so turned to so­tater­cept as the com­pa­ny re­port­ed pos­i­tive mid-stage da­ta in pa­tients with pul­monary ar­te­r­i­al hy­per­ten­sion (PAH). Un­like ex­ist­ing PAH ther­a­pies that are de­signed to di­late the pul­monary ar­ter­ies and re­duce blood pres­sure, so­tater­cept is en­gi­neered to re­store BM­PR-II sig­nal­ing, a key dri­ver of the dis­ease. If all goes well in piv­otal stud­ies, and the drug wins ap­proval — Porges es­ti­mates the drug could rake in glob­al sales of about $1.2 bil­lion in 2028.

“Af­ter that (FSHD) re­sult we re­moved all of the val­ue of this pro­gram from our mod­el and fore­casts, and for this rea­son, this (CMT) dis­clo­sure has no im­pact on our val­u­a­tion,” Porges said.

“It does con­firm that Ac­celeron in­vestors and man­age­ment were in­deed for­tu­nate that their so­tater­cept phase II tri­al in PAH had a pos­i­tive out­come, and the mag­ni­tude of the ben­e­fit in that tri­al, and the fu­ture de­vel­op­ment path, time­line and cost, be­come even more im­por­tant to the stock and its val­ue now.”

As Astellas continues its drive to build out its gene therapy portfolio and capabilities, a subsidiary of the Japanese pharma company has entered into a collaboration with a little-known Pittsburgh biotech.

Astellas-owned Mitobridge and Generian Pharmaceuticals announced on Wednesday that they will work together in a new deal for “undruggable” protein targets. Generian will net an undisclosed upfront payment and could get up to $180 million in milestones, should anything from its platform prove successful, as well as single-digit royalties on global net sales.

Three months separated from a disappointing readout of its Covid-19 vaccine, Icosavax is back with what it calls positive topline data for a different VLP vaccine candidate — although investors aren’t impressed.

IVX-121, a vaccine candidate for respiratory syncytial virus (RSV), appeared to generate “robust” immune responses among both young and older adults, as measured by neutralizing antibodies, and appeared generally well-tolerated, Icosavax reported.

As the House-passed bill to cap the monthly price of insulin at $35 nationwide makes its way for a Senate vote soon, Sanofi announced Wednesday morning that beginning next month it will cut the monthly price of its insulins for uninsured Americans to $35, down from $99 previously.

The announcement from Sanofi, which allows the uninsured to buy one or multiple Sanofi insulins (Lantus, Insulin Glargine U-100, Toujeo, Admelog, and Apidra) at $35 for a 30-day supply effective July 1, follows House passage (232-193) of the monthly cap in March, with just 12 Republicans voting in favor of the measure.