Wall Street analysts who follow Lilly were noticeably optimistic about donanemab after the company’s January announcement, with some speculating strong data could be enough for Lilly to ask the FDA for an accelerated approval. Shares in Lilly rose by double-digits on Jan. 11 and have continued to climb higher since.

But analysts and investors may be less bullish on donanemab upon seeing the full data. In their paper, study researchers suggested more work remains to be done to prove the drug.

“Longer and larger trials are required to study the efficacy and safety of donanemab in early Alzheimer’s disease,” they wrote.

Mintun, who was the paper’s lead author, indicated Lilly plans to discuss its data with regulators. “We are obviously interested in that conversation and interested in getting this drug to the patient as soon as possible,” he said. But the timing of those talks are “just not clear yet.”

Lilly will provide an update on its developments plans on a webinar planned for Monday morning. In a statement, Daniel Skovronsky, Lilly’s chief scientific officer, emphasized the company’s faith in its data.

“We are confident in the results of the TRAILBLAZER-ALZ study,” he said.