The U.S. Food and Drug Administration (FDA) declined to approve a new drug application for a second nasal spray version of the opioid overdose antidote naloxone, Reuters reports. The FDA approved a nasal spray version of naloxone last month.

Invidior, the manufacturer of the second drug, said in a news release that the FDA’s response “was principally focused on clinical pharmacology,” and said it is evaluating the agency’s comments to determine the company’s next steps.

Last month, the FDA approved a nasal spray version of naloxone, sold under the brandname Narcan. Until now, the only approved version of naloxone was injectable.

The company that makes the spray, Adapt Pharma, said it will offer the spray at a discount to emergency workers, police and firefighters.

Naloxone is used to reverse overdoses of opioids including prescription medications such as oxycodone, hydrocodone and morphine, as well as heroin. The FDA noted in a press release that if naloxone is administered quickly, it can counter the effects of an opioid overdose, usually within two minutes.

The injectable form of naloxone is generally delivered by syringe or auto-injector. Many first responders and caregivers say the nasal spray will be easier to deliver, and eliminates the risk of a contaminated needle stick. There has been widespread use of unapproved naloxone kits that include an injectable formulation of naloxone, with an atomizer that delivers the drug nasally, the FDA noted. “Now, people have access to an FDA-approved product for which the drug and its delivery device have met the FDA’s high standards for safety, efficacy and quality,” the agency stated.