Spero Therapeutics, a US-based biopharmaceutical company backed by corporates Alphabet, Partners Healthcare, GlaxoSmithKline, Merck & Co and Lundbeck, has raised $77m in its initial public offering.
The company issued 5 million shares on the Nasdaq Global Select Market priced at $14.00 each, at the foot of the IPO’s $14 to $16 range. The underwriters have a 30-day option to buy another 825,000 shares, which would lift the size of the offering to $88.6m.
Spero is working on drugs that will treat bacterial infections that have already proven resistant to multiple therapeutics, by enhancing the spectrum and potency of existing antibiotics.
Approximately $40m of the IPO proceeds will support a phase 1 clinical trial and phase 3 pivotal trial for Spero’s lead product candidate, SPR994, which is being developed to treat Gram-negative infections, caused by bacteria that is resistant to most drugs.
A further $18m will fund preclinical activities and a phase 2 clinical trial for SPR741, a treatment Spero is developing for pulmonary non-tuberculous mycobacterial infections. It will put $7m into development activities for two more candidates, SPR206 and SPR720.
The company had raised about $115m in funding, including $3m in 2014 from Partners Innovation Fund (PIF) and SR One, respective subsidiaries of healthcare provider Partners Healthcare and pharmaceutical firm GlaxoSmithKline, as well as venture capital Atlas Venture.
All three investors took part in Spero’s $30m series A round in 2015, alongside conglomerate Kraft Group, and MRL Ventures and Lundbeckfonden Ventures, which invest on behalf of pharmaceutical firms Merck & Co and Lundbeck.
The same six provided $30m more in February 2016 and returned for a $51.7m round in March 2017 also featuring GV, a corporate venturing vehicle for internet and technology conglomerate Alphabet, Osage University Partners, Rock Springs Capital and RA Capital Management.
Atlas Venture is Spero’s largest shareholder, with a 23.6% stake that was diluted to 14.2% in the IPO. Its other main investors are SR One (a 10.3% stake post-IPO), GV (8%), Lundbeckfond Invest (6.3%), MRL Ventures (5.3%), RA Capital (4.3%) and Osage (3%).
Unspecified existing shareholders expressed interest in buying $30m of the company’s shares as part of the offering, but it is unclear whether they did so. BofA Merrill Lynch, Cowen and Stifel are the joint book-running managers for the IPO while Oppenheimer & Co is co-manager.