Eli Lilly Is Acquiring a Psychedelic Medicine Biotech. Here's What You Need to Know.

Eli Lilly (NYSE: LLY) has spent the past two years reinvesting the cash flow from its spectacularly successful GLP-1 drug into building out its pipeline, and it just made a diversification play unlike any of the others it has made recently. On July 16, the company said it will acquire AtaiBeckley (NASDAQ: ATAI), a clinical-stage biotech developing psychedelic molecules intended to work as therapies for hard-to-treat mental illnesses.

With the deal expected to close in September, Lilly will pay nearly $2.8 billion, with another $1 billion possible through milestones.

That's especially surprising considering that psychedelic medicine spent the past two years being written off as a dead zone after regulatory setbacks, only to now be increasingly mainstreamed by a federal policy pivot. Here's what you need to know about how the purchase of Atai is going to affect the investment thesis for Eli Lilly.

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There's more than one pipeline program being acquired here

Atai's centerpiece is BPL-003, a nasal spray formulation of the molecule mebufotenin, which is better known as 5-MeO-DMT, a short-acting psychedelic in the same family as the powerful dimethyltryptamine (DMT).

BPL-003 is heading into phase 3 trials for treatment-resistant depression (TRD). And right behind it in the pipeline are VLS-01, a buccal film of DMT (designed to dissolve on the inside of a patient's cheek) that's also aimed at TRD, and EMP-01, an oral R-MDMA candidate for treating social anxiety, both of which are in Phase 2. Those programs will round out Lilly's neuroscience portfolio, which already has six clinical-stage programs for behavioral health and addiction disorders.

The strategic logic is fairly legible here. Management is on pace to bring in $82 billion to $85 billion in revenue for 2026, much of it from its GLP-1 superstars Mounjaro and Zepbound, and now diversification via bolt-on acquisition is the name of the game.

The business made four other acquisitions in the first quarter alone, across a variety of different disease areas. AtaiBeckley extends that pattern into neuroscience.

The catch is that Lilly's sheer scale makes it tough to have high hopes for Atai's programs to have much of an impact on the top line if they're ever commercialized.

The data looks good, but there are other issues

Atai's lead candidate has generated some compelling data. At Day 29 of BPL-003's phase 2b trial, patients on the 12 milligram (mg) dose showed an 11.1-point drop on the Montgomery-Asberg Depression Rating Scale (MADRS) versus 5.8 points on a 0.3 mg low-dose active control, a 5.3-point placebo-adjusted difference.

The 8 mg dose is what's moving into phase 3, based on a cleaner tolerability profile. That delta is broadly comparable to placebo-adjusted MADRS reductions reported for the few established TRD treatments.

But GH Research, which is developing an inhalable version of the same molecule, posted even better results: a 15.5-point placebo-adjusted MADRS reduction, in its own phase 2b trial results this year. Cross-trial comparisons are often sketchy and difficult to do rigorously, but in this case, the magnitude gap is hard to ignore; Atai's candidate currently appears to be the weaker of the two.

Another one of Atai's competitors, Compass Pathways, is further along still. It has in hand two positive data sets from phase 3 trials of its psilocybin formulation COMP360 for TRD, and it's formulating a regulatory submission that's currently on track for the fourth quarter of 2026.

BPL-003 is a real asset with legitimate data. But given the competition, Lilly has effectively paid a premium to try to enter a market using a second- or third-in-class option rather than something that could obviously capture a large market share.

The regulatory backdrop, on the other hand, has meaningfully improved. On April 18, President Donald Trump signed an executive order directing the U.S. Food and Drug Administration to prioritize the review of psychedelic medicine candidates with Breakthrough Therapy designations.

The agency subsequently issued national priority vouchers to Compass Pathways and a couple of other businesses. BPL-003 already holds Breakthrough Therapy status, so it plausibly could qualify for the same treatment if the phase 3 results are good enough to attempt to proceed with commercialization.

Still, Lilly shareholders should not treat this acquisition as a path to guaranteed earnings growth. BPL-003's phase 3 data is years away. Any contribution to growth is further out than that, and it will all depend on whether BPL-003 can clear the very same regulatory bars that are actively changing at the moment.

Alex Carchidi has no position in any of the stocks mentioned. The Motley Fool has positions in and recommends Eli Lilly. The Motley Fool has a disclosure policy.