Aptinyx, Magenta lead biotech IPO flurry ahead of summer lull

No fewer than five biotech IPOs debuted Thursday, raising more than $460 million and with more in the offing if underwriters take up further options.

The spate of biotech public listings—accounting for five of 12 IPOs this week—might suggest companies are trying to wrap things up ahead of the summer quiet period. But with 2018 looking already like it may overtake 2017’s bumper crop, the next few weeks may not be quite so quiet.

Heading the pack by money raised is Aptinyx ($APTX), raking in just over $102 million from a $16 offering to advance its glutamate NMDA receptor-targeting drugs for neurological disorders. Its pipeline is headed by NYX-2925, due to have a phase 2 readout in pain associated with diabetic neuropathy and fibromyalgia in the first half of 2019.

Chronic pain trials are costly and Aptinyx will need plenty of cash to take that project through phase 3. So it will be delighted to top its earlier $80 million estimate for IPO proceeds. The IPO comes shortly after Allergan exercised an option to acquire rights to NMDA depression candidate AGN-241751,

Second up is stem cell biotech Magenta Therapeutics ($MGTA) which came in bang on target with its IPO, raising $100 million from its $15 placement. The company is focusing on multiple ways to improve hematopoietic stem cell transplants (HSCT) so that more patients can be treated with the sometimes-dangerous therapy, and its pipeline is headed by an ex-Novartis drug designed to expand stem cells outside the body and improve the dose that can delivered in HSCT. The new money will help fund a pivotal trial of that drug (MGTA-456), as well as trials of other candidates to mobilize stem cells from the bone marrow to the blood and prevent post-transplant complications.

Just behind the top pair comes Atlas Venture-backed Avrobio ($AVRO), a specialist in lentiviral-based gene therapies that is pitching to disrupt the $4 billion market for drugs to treat rare lysosomal storage disorders like Fabry and Gaucher disease from the likes of Sanofi/Genzyme, Shire, and Pfizer. Its $19 listing raised $99.7 million, ahead of the $86 million Avrobio said it was aiming to make when it filed registration documents last month, and comes after the startup raised $60 million in a second-round fundraising in February. First up in its pipeline is AVR-RD-01 for the treatment of Fabry disease, which recently started a phase 2 study and could provide a one-shot alternative to current chronic treatments to control symptoms.

Drug delivery company Xeris Pharmaceuticals ($XERS) also enjoyed an upsized IPO, raising $85.5 million at $15 per share, to help fund continued development of its ready-to-use glucagon rescue pen for diabetes patients who go into severe hypoglycaemia—in phase 3—as well as other glucagon formulations in midstage testing and an artificial pancreas in early development. It previously set a target of $75 million from the listing.

Finally, Kezar Life Sciences ($KZR) rounded out the bumper day by raising $75 million at $15 per share for its pipeline of immunoproteasome inhibitor drugs for autoimmune diseases headed by KZR-616, a small-molecule drug in a phase 1b/2 trial in lupus and lupus nephritis. In addition to funding that study, the new cash will also help the company start up to three additional trials in idiopathic inflammatory myopathies and other autoimmune diseases.