US regulatory advisors are backing clearance of Allergan's SER120, a low-dose nasal formulation of desmopressin designed to treat night-time urination.

The Bone, Reproductive and Urologic Drugs Advisory Committee has voted 14-4 in favour of approving the therapy for nocturia, the need to wake and pass urine at night on more than two occasions, Reuters has reported.

However, the panel has reportedly recommended that the US Food and Drug Administration restrict SER120's use to a subset of patients who have nocturnal polyuria - when there is an increase in nighttime urine production with a corresponding drop in daytime production, resulting in a normal 24-hour urine volume.

In briefing papers posted to the Agency's website ahead of the meeting, it was noted that post hoc analyses suggest that patients with nocturnal polyuria might have a slightly greater response to SER120 than those without.

Dublin, Ireland-based Allergan picked up exclusive rights to develop and commercialise the drug from Serenity Pharmaceuticals back in 2010.

Meanwhile, the group also announced early termination of the Hart-Scott-Rodino waiting period for Allergan's proposed acquisition of Tobira, satisfying one of the conditions to completing the acquisition.

Allergan revealed last month its intention to buy the firm for $1.7 billion; both companies expect the transaction to be completed by the end of 2016.