An agency advisory committee narrowly backed Johnson & Johnson’s Doribax as a treatment against pneumonia, despite serious concerns about how the drugmaker studied the med, the Associated Press reports. The panel voted 7-6 that Doribax is effective at treating hospital-acquired pneumonia, and a majority also decided the antibiotic seems safe for patients.

“I can’t come up with a clear difference that would make (Doribax) different from all the other ‘me-too’ drugs that came before it,” panelist James Leggett, an Oregon Health Sciences University professor said during the meeting. However, the panel also voted 9-4 against accepting J&J studies, complaining they were not statistically rigorous enough to prove the drug works as well as older therapies.

J&J based its application for Doribax on two studies designed to show the antibiotic worked at least as well as two older antibiotics, but FDA medical reviewers indicated there were several problems with the studies that made it difficult to conclude whether Doribax is as good as existing therapies. Doribax is already approved to treat infections of the inner-abdomen and urinary tract.

J&J evaluated Doribax based on chest X-rays of pneumonia patients before and after they received the injectable drug. But the government’s review “revealed cases in which patients with worsening chest X-rays were evaluated as cures,” the AP notes. FDA reviewers also said they were concerned the company did not submit the test results which it used to identify patients with pneumonia.

One panel member said the FDA should not lower the bar simply because larger trials would require more work from companies. “If we introduce antibiotics that aren’t effective because they haven’t been rigorously tested, I don’t see how that benefits patients,” said Thomas Fleming, a professor of biostatistics at the University of Washington.