Reports: AstraZeneca makes ~$10B offer for rare-obesity drugmaker Rhythm Pharmaceuticals

What's the news? AstraZeneca has made a non-binding offer of about $10 billion to acquire Rhythm Pharmaceuticals, according to three people familiar with the matter cited by Reuters on 4 November 2026. The proposal values Rhythm at up to $134 per share including milestone payments; the Wall Street Journal had earlier reported a $124-per-share offer.

Context: The deal would run through Alexion, the rare-disease specialist AstraZeneca bought for $39 billion in 2021, and would give the pharma group an established position in rare genetic forms of obesity — a fast-growing corner of the weight-management market. Rhythm's approved therapy Imcivree (setmelanotide) treats rare obesity caused by specific genetic defects, and in March 2026 the FDA expanded its use to obesity caused by brain damage (hypothalamic obesity). An acquisition is not confirmed: neither company has commented, and the offer is reported rather than formally announced.

Why it matters: For AstraZeneca, a deal would bolster its rare-disease and specialty-medicines portfolio after a period of clinical setbacks, as chief executive Pascal Soriot looks to refocus investors on growth. For Rhythm, it would be a validating outcome for a company built around treating severe, hard-to-treat forms of obesity.

Read more: Reuters via WHBL, 4 November 2026