LONDON — AstraZeneca’s reported pursuit of Rhythm Pharmaceuticals would buy a foothold in rare forms of obesity, rather than an immediate challenger in the mass-market weight-loss business. The distinction matters to a proposed price of about $10 billion for a company whose latest quarterly product revenue was $92.1 million.
Reuters reported on November 4, citing three people familiar with the matter, that AstraZeneca had made a non-binding proposal worth as much as $134 a share, including payments tied to milestones. AstraZeneca declined to comment to Reuters, while Rhythm did not respond to the agency’s request. Neither response establishes an agreed transaction.
The potential acquisition would run through Alexion, AstraZeneca’s rare-disease business, according to two of Reuters’ sources. That route gives the story a different commercial logic from the race to sell weight-loss medicines to the broadest possible population: Rhythm already has a marketed therapy for narrowly defined conditions, alongside an expanding development programme.
The Reuters report carried by Yahoo Finance put Rhythm’s November 4 closing share price at $110.68, up 28%, with a market value of about $7.64 billion. The rally shows investors responding to the reported approach. It does not resolve how much cash a shareholder would receive at closing, whether the milestones would be achieved, or whether a deal will happen.
Rhythm’s November 3 results offer a more concrete starting point for assessing what a buyer might acquire. Global net product revenue from Imcivree, its setmelanotide treatment, reached $92.1 million in the third quarter, up 29% from the second quarter and from $51.3 million a year earlier. Those are company-reported sales, not an estimate of a future market.
The quarterly financial disclosure said U.S. revenue was $67.5 million, or 73% of product revenue. Rhythm attributed the sequential U.S. increase primarily to demand in acquired hypothalamic obesity, alongside continued demand in Bardet-Biedl syndrome. The growth is therefore tied to particular diagnoses, not evidence of a general weight-loss prescription business.
Acquired hypothalamic obesity can follow injury to the brain region involved in regulating hunger and body weight. Rhythm said the U.S. Food and Drug Administration approved Imcivree for that condition on March 19, and that it had received more than 700 patient start forms from more than 500 prescribers by September 30.
A start form is not the same measure as a reimbursed patient or a completed course of treatment. Rhythm separately reported that the global number of patients on reimbursed therapy rose 20% from the second quarter. Keeping those measures apart prevents the launch figures from being read as a simple count of people already generating revenue.
For shareholders, the valuation still asks for substantial growth beyond the current sales base. Multiplying third-quarter product revenue by four produces an annualised pace of $368.4 million. A $10 billion headline offer is roughly 27 times that amount, a calculation based on the reported proposal and Rhythm’s published revenue.
That is a scale comparison, not a forecast or an enterprise-value multiple. It assumes the quarter repeats unchanged, takes no account of cash, debt or the full terms of a transaction, and combines a headline offer with a sales measure. Rhythm’s 29% sequential growth also shows why a static annualisation can quickly become dated.
The milestone component adds another limit. Reuters said the proposal could reach $134 a share including contingent payments; it did not set out the milestones in its report. Treating that maximum as an unconditional cash price would erase a material uncertainty for investors. The structure and triggers of those payments remain undisclosed in the sources reviewed.
Alexion provides the strategic link. AstraZeneca acquired the rare-disease company for $39 billion in 2021, Reuters reported. Buying Rhythm through that business would add an existing commercial product and specialist patient populations, rather than requiring AstraZeneca to build the entire rare-obesity franchise from an early research asset.
Commercial progress has not yet made Rhythm profitable. Its third-quarter net loss attributable to common shareholders was $42.4 million. Research and development spending was $52.5 million, while selling, general and administrative expenses were $66.8 million. A prospective owner would be acquiring the costs of expanding the business as well as its rising revenue.
Rhythm’s chief executive David Meeker said in the results announcement that the strength of the U.S. launch reinforced both unmet need and the company’s commercial opportunity. That is management’s assessment. The published sales provide evidence of demand, but they do not establish the size of the eventual treated population or how long the current growth rate will persist.
The company also said a commercial launch for acquired hypothalamic obesity was underway in Japan and that it expected to begin a pivotal Phase 3 study of bivamelagon in the condition by year-end. That timetable is a company expectation, not a completed trial or a guarantee of approval.
The offer report leaves two different uncertainties standing together. Rhythm has disclosed a growing rare-disease business; AstraZeneca has not publicly explained what it is willing to pay for that growth. Even the reported maximum per-share figure depends on milestones whose terms have not been disclosed.
