Recently Pfizer announced that it would acquire Metsera in a deal valued at $7.3 billion for its development of drugs treating patients with obesity and other metabolic disorders. However, the stipulation laid out is that the initial amount at closing of this deal is set to be $4.9 billion, or $47.50 per share. This is just the way the deal was structured to start off with this value. In essence, the remaining $22.50 is only to be obtained based on the trigger of a non-contingent value right (CVR). Although, this CVR is not going to come about easily because the only way each part gets triggered is if certain clinical and regulatory milestones are met. This includes separate CVRs to be achieved based on milestones ranging from FDA approvals to initiation of a phase 3 study testing the use of MET-097i in combination with MET-233i. Should this deal satisfy certain conditions, then it is expected to be completed in the fourth quarter of 2025.
The acquisition of Metsera for Pfizer comes at the most opportune moment, specifically because the biotech was set to release several key data sets over the next several months. The goal was to release data from a few phase 2b studies for the development of MET-097i and also phase 1 data for MET-233i as well. With that being said, the lead program made use of GLP-1 receptor agonist (GLP-1 RA) MET-097i in the phase 2b studies known as VESPER-1 and VESPER-3. Beyond this move, it was already in the planning process to initiate a phase 3 study using this ultra long-acting GLP-1 RA to treat patients with obesity in late 2025.
The important reason why these GLP-1 drugs work well as agonists is because they mimic a naturally occurring glucagon-like peptide-1 (GLP-1) after a person has finished eating. This is not the only reason why this class of drugs is ideal; consider that it causes the pancreas to produce more insulin, and in turn, this lowers elevated levels of blood sugar. You can see how this restores blood glucose balance for a person. Other modes of action that occur with GLP-1 activation are delayed gastric emptying and satiety (feeling of fullness). With that being said, I don’t believe this acquisition came blindly, in that Metsera offers the ability to develop nutrient stimulated hormone (NuSH) analog peptides.
The importance of this is that current NuSH peptides face limitations. However, Metsera has been able to develop improved versions of NuSH and this is thanks to its HALO platform. This specific technology is composed of its peptide lipidation technology, and the point of it is to extend the half-life of the NuSH peptide analogs it is developing. The reason why this is a crucial part of the company’s development pipeline is because it allows it to develop MET-097i and MET-233i to be dosed to patients as a once-monthly subcutaneous (SC) injection. This could provide a competitive advantage over other existing GLP-1 RA drugs that are currently approved, like Zepbound (tirzepatide) from Eli Lilly and Wegovy (semaglutide) from Novo Nordisk.
The point is that these FDA-approved drugs for weight loss have to be taken as once-weekly SC injections. If Metsera can get its MET-097i drug to be dosed once-monthly for patients, then this could give it a competitive edge. Even more so if it is able to do what is incorporated into its HALO technology platform, which is improved tolerability. Other advantages in place are lower active pharmaceutical ingredient (API) being required for it and titration-free dosing. This acquisition was not likely made solely on MET-097i, it had even made significant progress with another class of drugs being developed to treat patients with obesity, and these are known as amylin analogs.
The amylin drug that this company is working on is known as MET-233i. In a phase 1 study, it was shown that this drug in a 5-week period was able to establish placebo-subtracted mean weight loss of 8.4% at day 36. This is important not only because this drug performed well in this early-stage study, but also because it achieving comparable weight loss to that seen in leading GLP-1 medicines. The scope of this positive data is that there is already a move to combine the use of MET-097i with MET-233i as a once-monthly dosing regimen in a phase 1 study. Metsera stated that it intended to release 12-week monotherapy MET-233i data in late 2025. The 12-week combination data is slated for around the same time (end of 2025) or early 2026.
The HALO technology platform established proof-of-concept again with the potential with once-monthly dosing with MET-233i and this is thanks to the observed half-life of 19 days for it. It remains to be seen if having ultra long-acting NuSH therapies allows it to establish market share and overcome competitors with drugs in development or approved to treat these patients with obesity. The opportunity for Metsera I laid out above, though, doesn’t even dive into the fact that it is already in the process of developing ultra long-acting oral GLP-1 RA peptides, which are MET-097o and MET-224o. The goal is to have 4-week data from each of these candidates in late 2025.
However, it is important to note that these oral drugs candidates are being developed with another type of technology from Metsera, known as MOMENTUM. The purpose of deploying this is to increase drug absorption of its NuSH peptide analogs. The thing is that peptides have been tough to use as oral drugs for weight loss and this is because of the requirement of high dosage being necessary to achieve a desired effect. With that being said, this technology helps the company to overcome this problem and test the use of its drugs with lower dosing compared to other NuSH peptides in clinical drug development. This transaction was not met with any hostility whatsoever, in that both Boards of Directors of Metsera and Pfizer unanimously approved this transaction.
Pfizer needed to do something to incorporate into its pipeline in terms of drug development for obesity patients. The reason why is because of a setback it had with the development of its GLP-1 RA drug danuglipron. It suffered a setback at first with a twice-daily version of this drug in 2023, and then in April of this year it chose to discontinue a once-daily formulation of it as well. It remains to be seen if this acquisition was the right move for it, but at least it adds an extensive obesity drug pipeline that it can work with.