ARS Pharmaceuticals has signed a definitive agreement to merge with Silverback Therapeutics in an all-stock transaction.

The combined company will operate under the name ARS Pharmaceuticals and be headquartered in San Diego, California, US, after the completion of the transaction.

It will focus on the potential regulatory clearance and commercialisation of ARS’ investigational epinephrine nasal spray, neffy.

The needle-free, low-dose intranasal epinephrine nasal spray is currently under clinical development.

It was designed for providing injection-like epinephrine absorption in an easy-to-use, easy-to-carry, quickly administered nasal spray device.

ARS co-founder and CEO Richard Lowenthal said: “neffy is on the cusp of achieving what has not been possible before – the ability to deliver epinephrine with comparable pharmacokinetics to intramuscular injection, but with a simple to administer nasal spray.

“We have completed a comprehensive registration programme with neffy and based on a favourable pre-NDA meeting with the US Food and Drug Administration (FDA), we are preparing to submit our New Drug Application (NDA) in the third quarter of 2022.

“This merger positions ARS and our experienced team to execute on the potential launch of neffy in 2023 by providing the requisite capital needed for launch.”

Upon closing the deal, which is expected to be completed in the fourth quarter of this year, the combined company is estimated to have nearly $265m in cash, cash equivalents and marketable securities and $240m in Silverback’s net cash.

On a fully diluted basis on a treasury stock method, Silverback equity holders will own nearly 37% and pre-merger ARS equity holders will own about 63% of the combined company.