Translate files for $115M IPO to trial ex-Shire mRNA cystic fibrosis treatment

Translate Bio has filed to raise $115 million from public investors. The IPO will tee Translate up to trial an mRNA candidate designed to enable all cystic fibrosis patients to produce fully functional CTFR proteins.

Lexington, Massachusetts-based Translate is built upon an mRNA therapeutic platform it bought from Shire late in 2016. The deal transferred the platform, its scientific founders and product candidates to Translate, which has since progressed the most advanced asset into the clinic. That done, Translate is seeking $115 million to fund clinical trials in cystic fibrosis and OTC deficiency.

Having been held up by a CMC-related clinical hold, Translate began a phase 1/2 trial of MRT5005 in cystic fibrosis last month. The study will enroll 32 patients and randomize them to receive either its mRNA therapy or placebo. Translate is looking to the trial for evidence of the safety of MRT5005 and its ability to deliver mRNA to epithelial cells. 

The asset consists of an mRNA sequence packaged in a lipid-based nanoparticle. The size and lipid composition of the nanoparticles are designed to enable them to get mRNA into lung cells when delivered via a nebulizer. Preclinical studies suggest the drug is suitable for repeat dosing, an important consideration given the turnover of epithelial lung cells. 

Translate is some way off from generating clinical data to support the idea, with the multiple ascending dose stage of the blinded study still months away from starting. But, having dosed one patient in the single ascending dose stage, Translate already has a safety signal serious enough to warrant bringing up in its IPO filing. 

The patient developed transient, flulike symptoms that responded to treatment. As the trial is blinded, Translate has yet to learn whether the patient is on MRT5005, but other studies of nebulized nanoparticles have reported similar symptoms. 

Translate, formerly known as RaNA Therapeutics, had expected to be in the clinic last year but took a detour. In 2015, RaNA raised $55 million, setting it up to move oligonucleotide treatments for spinal muscular atrophy and Friedreich’s ataxia into human testing starting in 2017. 

RaNA pivoted away from the plan 12 months ago when it decided to dial down its oligonucleotide work and make the platform it bought from Shire its top priority. By the first quarter of 2018, spending on oligonucleotides had fallen to $69,000. The cystic fibrosis program went through more than $4 million over the same period.

The preclinical pivot has contributed to Translate chewing through $170 million to date. As RaNA, the biotech received money from Atlas Venture Fund and GlaxoSmithKline’s and Merck’s VC wings, among others. The three funds each own more than 5% of Translate. Shire owns almost 20% of the biotech and, under the terms of its contract with Translate, is set to add to its holdings through the IPO.