(Adds details on safety, background)
By Natalie Grover
Oct 17 The proposed dosing for a drug being
developed by Allergan Plc to treat frequent urination at
night has not been adequately studied in trials, a preliminary
review by the U.S. Food and Drug Administration staff concluded.
The drug, SER120, is a low-dose nasal version of the
commonly used treatment, desmopressin, and is designed to treat
adults with nocturia, a disorder where a person wakes up to
urinate twice or more at night.
There are no FDA-approved drugs to specifically treat
Allergan has proposed starting patients with a 0.75
microgram (mcg) dose, and moving up to 1.5 mcg if necessary, but
this dosing regimen was not studied in any clinical trials,
staff reviewers said on Monday. (bit.ly/2dIxcrs)
In addition, late-stage data showed that only the higher
dose met the statistical criteria for efficacy. The "clinical
meaningfulness" of the drug's benefit was also unclear when
compared with a placebo, the reviewers said.
Desmopressin was first approved in the United States in 1978
to treat patients with diabetes insipidus, a rare disorder that
causes an imbalance of water in the body.
Since then, the FDA has sanctioned the drug's use in other
An oral desmopressin pill from privately held Ferring
Pharmaceuticals has been rejected twice by the FDA, which said
the risk of hyponatremia, or abnormally low sodium levels in the
blood, outweighed the drug's benefit.
The FDA had asked Allergan to enroll patients aged at least
50 to better assess the risk of hyponatremia, which is greater
in the elderly, in its late-stage trials for SER120.
However, since the company is seeking approval for adults
regardless of age, efficacy in patients younger than 50 has not
been assessed, the staff said.
Of the five deaths among patients on SER120 during clinical
trials, the role of the drug cannot be definitively ruled out in
two, the reviewers said.
Four of the five deaths were in patients older than 75.
Nocturia is a considered a symptom of one or more underlying
conditions such as obstructive sleep apnea, diabetes mellitus
and congestive heart failure.
The review comes two days ahead of a meeting of outside
experts who will recommend to the FDA whether to approve the
The agency is not obliged to follow its advisory panel's
recommendations but typically does so.
Allergan in 2010 acquired from privately held Serenity
Pharmaceuticals exclusive rights to develop, manufacture and
sell the drug for all potential indications, excluding
bedwetting in children.
The company's shares were down 1.3 percent at $224.42 in
(Reporting by Natalie Grover in Bengaluru and Toni Clarke in
Washington; Editing by Sriraj Kalluvila)