UPDATE 2-Canada's Appili gets US FDA approval for oral antibiotic solution

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Sept 25 (Reuters) - The U.S. Food and Drug Administration (FDA) on Monday approved Canadian drugmaker Appili Therapeutics' liquid oral form of antibiotic drug metronidazole, offering an alternative to patients who have difficulty taking injections or pills.

An injectable form of the drug, which is commonly used in the treatment of bacterial and parasitic infections, has been in shortage in the United States since early last year due to high demand and regulatory delays.

Appili said its partner, privately-held Saptalis, will sell the newly approved form of the drug under the brand name Likmez in the United States.

The approval of Appili's drug could help ease the metronidazole shortage, especially for patients in hospitalized settings and those with severe infections, who are affected most by the shortfall.

"It won't completely solve the shortage but it could be very helpful," said Erin Fox, senior director of drug information at the University of Utah Health.

But some experts were divided about the impact of the approval.

"The liquid form will be useful for certain types of infections, but it may not replace the intravenous formulations. So it will help a certain amount of patients," said David Margraf, a pharmaceutical research scientist at the University of Minnesota's Center for Infectious Disease Research & Policy (CIDRAP).

According to Appili, there are more than 10 million U.S. prescriptions annually for the drug.

The number of U.S. drugs in shortfall - at 309 by the end of the second quarter - is already near a 10-year peak, according to the American Society of Health-System Pharmacists, compared with an all-time high of 320 drugs.

Last week, an FDA spokesperson said the agency was working closely with numerous manufacturers and others to mitigate the impact of irregular or increased demand for certain products, but the regulator did not comment on the metronidazole shortage.

(Reporting by Bhanvi Satija in Bengaluru; Editing by Shweta Agarwal and Devika Syamnath)