Pfizer Finalizes $65.60/Share Acquisition of Weight Loss Drugmaker Metsera (MTSR Merger)

On November 13, 2025, Pfizer officially completed its acquisition of Metsera, Inc., closing one of the most high-profile biotech deals of the year. The merger, initially announced in September and amended in November, brings Metsera under Pfizer’s umbrella through an all-cash transaction worth $65.60 per share, plus potential additional payments through contingent value rights (CVRs). This transaction not only reshapes the weight-loss drug development landscape but also marks a strategic win for Pfizer’s long-term growth ambitions in metabolic therapies.

Here’s an updated breakdown of the final terms, CVR details, legal aftermath, and what shareholders and market watchers need to know.

Deal Structure: Now Finalized

As of the effective time of the merger:

• Metsera shareholders received $65.60 per share in cash, without interest and subject to tax withholdings

• Shareholders also received one CVR per share, which may provide up to $20.65 in additional payouts

• All common stock of Metsera ceased trading after the market closed on November 13, 2025

The company’s shares were delisted from Nasdaq, and Metsera filed to deregister its securities with the SEC, making it a wholly owned subsidiary of Pfizer.

CVRs: Milestone-Based Payments

Each CVR represents a contractual right to receive additional cash if Metsera hits certain drug development and regulatory targets:

1. $4.60 Payment If a Phase 3 trial begins for the MET-233i and MET-097i combination therapy by December 31, 2027

2. $6.40 Payment Upon FDA approval of MET-097i as a monotherapy for chronic weight management by December 31, 2029

3. $9.65 Payment Upon FDA approval of the combination product MET-233i and MET-097i by December 31, 2031

Pfizer is no longer obligated to spend $1.5 billion on clinical development under the revised CVR agreement. Instead, it must use commercially reasonable efforts to achieve the milestones.

Treatment of Equity Awards

The finalized agreement included detailed handling of Metsera’s outstanding equity instruments:

• Stock Options

  • In-the-money options were converted into a cash payment (based on the difference between the option price and $65.60), plus CVRs

  • Unvested options follow the original vesting schedule, with added double-trigger vesting protection

• Restricted Stock Awards

  • Immediately vested and converted into the full merger consideration

• Restricted Stock Units (RSUs)

  • Converted into a cash payout based on the $65.60 price, plus an equal number of CVRs

  • Retain the same vesting schedule and include change-of-control protections

This means that even employees with unvested awards may benefit from the transaction over time, assuming continued employment and milestone success.

Legal and Market Changes

Lawsuits and Legal Developments

As previously reported, several shareholder lawsuits were filed to challenge the merger’s fairness and disclosure quality. Pfizer also pursued legal action against Metsera's board and external players like Novo Nordisk. However, the Delaware court denied Pfizer’s request for a temporary restraining order, and the merger proceeded to close on schedule.

The amended merger agreement included release provisions shielding Metsera from certain legal claims, though broader litigation remains possible depending on post-merger developments.

Delisting and Deregistration

Effective November 13, 2025:

• Trading of MTSR ceased on Nasdaq

• Nasdaq received notice to withdraw the listing and filed Form 25 with the SEC

• Metsera will also file Form 15 to suspend its reporting obligations

This marks the full transition of Metsera from a public company to a private Pfizer subsidiary.

Shareholder Vote Outcome

The shareholder vote took place virtually on November 13, 2025. While specific vote tallies were not disclosed, Metsera confirmed that the required majority voted in favor of the amended merger agreement and related proposals, allowing the transaction to proceed.

Strategic Implications for Pfizer

Pfizer’s acquisition is widely seen as a bet on the booming obesity and metabolic drug market. By securing rights to MET-097i and MET-233i, the company aims to compete directly with sector leaders in the GLP-1 space and beyond.

The milestone-based CVR structure not only gives Pfizer flexibility on capital outlay but also aligns with long-term R&D success. If milestones are met, shareholders could see a total return of over $86 per share, significantly above pre-merger trading prices.

Final Word

With the merger now complete, Pfizer expands its pipeline with promising assets in the metabolic health arena. The transaction reflects growing confidence in the obesity drug market and highlights Pfizer’s strategy to regain momentum through targeted acquisitions. For Metsera shareholders, the immediate premium and milestone-based upside offer a compelling outcome, albeit one tied to future clinical success.

FAQs

Is the merger now finalized?

Yes. The transaction officially closed on November 13, 2025.

How much did shareholders receive?

$65.60 in cash per share, plus one CVR per share that could be worth up to $20.65 depending on future milestones.

What happens to Metsera stock?

It has been delisted from Nasdaq and will no longer trade publicly.

Can I still receive the CVR payments?

Yes, if you held eligible shares at the time of the merger and the outlined drug development milestones are achieved.

Are CVRs guaranteed?

No. Payments are contingent upon meeting regulatory and clinical development milestones.

What happens to employees’ unvested equity awards?

They retain their vesting schedules and include enhanced protections post-merger. Some awards will convert into future cash and CVR benefits.

Can shareholders seek appraisal?

'Yes, under Delaware law, shareholders who didn’t vote in favor and properly demanded appraisal may pursue a court-determined fair value instead of receiving merger consideration.

Pfizer Metsera MTSR Merger

Pfizer Metsera MTSR Merger

Financial Disclaimer

This article is for informational purposes only and does not constitute financial, investment, or legal advice. The content is based on publicly available filings and reports as of the date of publication. Readers should consult with licensed financial advisors, legal professionals, or tax experts regarding their individual circumstances. The author and publisher assume no liability for actions taken based on this content.