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April 3 (Reuters) - Insys Therapeutics Inc on Monday reported a 41.6 percent decline in quarterly revenue, hurt by a fall in demand for Subsys, an opioid spray approved for managing pain in cancer patients.
Arizona-based Insys is among the top U.S. opioid drugmakers by sales, and has come under scrutiny as authorities and lawmakers step up efforts to tackle the country's deadly opioid crisis.
Insys said revenue fell to $54.9 million in the fourth quarter ended Dec. 31, driven mainly by a 32 percent decline in prescriptions for Subsys, an under-the-tongue spray that contains the synthetic opioid fentanyl.
The Drug Enforcement Administration has voiced concerns about the dangers of fentanyl, an opioid prescribed as a pain reliever for terminally ill patients, but also produced in underground labs as a street drug.
Six former Insys executives and managers were arrested by U.S. prosecutors in December on charges of being engaged in a nationwide scheme to bribe doctors to prescribe Subsys.
Insys' results come days after the drugmaker said it would restate some financial statements after identifying errors related to accounting for some product sales allowances.
Insys also said on Monday it would not hold a call with analysts following its fourth-quarter report.
The company reported a net loss of $3.7 million or 5 cents per share in the fourth quarter, compared with a profit of $18.1 million or 24 cents per share, a year earlier.
Insys last week named Saeed Motahari its chief executive, effective April 17. Motahari joins Insys from Purdue Pharma, where he was chief commercial officer. (Reporting by Divya Grover in Bengaluru; Editing by Sai Sachin Ravikumar)