• Home
  • Latest
  • Fortune 500
  • Finance
  • Tech
  • Leadership
  • Lifestyle
  • Rankings
  • Multimedia
Biotech Industry

Why Sanofi Is Buying a U.S. Cancer Biotech for Nearly 3 Times Its Market Value

By
James Paton
James Paton
and
Bloomberg
Bloomberg
Down Arrow Button Icon
By
James Paton
James Paton
and
Bloomberg
Bloomberg
Down Arrow Button Icon
December 9, 2019, 6:00 AM ET

French pharma giant Sanofi agreed to buy U.S. biotech company Synthorx Inc. for $2.5 billion, almost triple its market value, accelerating a push into cancer under new Chief Executive Officer Paul Hudson.

Sanofi will pay $68 a share in cash for Synthorx, the companies said Monday. Shares of the unprofitable San Diego-based company closed at $25.03 Friday, having surged 40% last week.

The deal underscores the Paris-based drugmaker’s efforts to build its portfolio of innovative therapies in the fast-growing and lucrative cancer field. It was unveiled a day before Hudson outlines his pipeline and acquisition priorities, along with his initial plans for the consumer-health, diabetes and other units. The purchase marks Sanofi’s first multibillion acquisition since early 2018.

Investors are counting on Hudson to fire up Sanofi’s research operations and step up the search for novel products to reduce its reliance on Dupixent, a standout medicine for severe eczema and asthma. Hudson, the former pharma head at Novartis AG, is credited with launching key medicines at his previous job before becoming CEO of Sanofi in September.

The purchase is the latest sign of big pharma’s increasing bet on oncology medicines with drugmakers including Roche Holding AG, Bristol-Myers Squibb Co. and Merck & Co. leading the pack. Big premiums have become the norm as companies place riskier bets on acquiring potentially lucrative treatments from biotech startups.

Other Deals

Another company in catch-up mode, GlaxoSmithKline Plc, paid about $5.1 billion early this year for Tesaro, the maker of a promising cancer medicine called Zejula. The U.K. drugmaker’s new CEO, Emma Walmsley, has doubled the number of experimental cancer drugs in human testing to 16. Three of those could reach the market next year.

Synthorx’s main drug, known as THOR-707, is being explored as a treatment for multiple types of solid tumors, together with immune checkpoint inhibitors and other future combinations.

Sanofi shares fell as much as 0.6% on Monday.

The French drugmaker earlier this year said it would accelerate 17 drug programs, almost half in cancer, and drop more than a dozen others under development. Analysts at HSBC wrote in August that more deals would be the fastest way to build up Sanofi’s stable of medicines and profile in cancer. Sanofi and partner Regeneron Pharmaceuticals Inc. won approval last year for an immune-oncology drug — Sanofi’s first — for a deadly form of skin cancer.

In another sign of rising deal activity in the biotech sector, Astellas Pharma Inc. last week agreed to buy Audentes Therapeutics Inc. for about $3 billion, paying a 110% premium to advance into the gene therapy realm.

Sanofi shares have climbed about 11% since Hudson was named CEO in June, closing at 83.56 euros on Friday. The stock had declined almost 16% over the previous four years.

Morgan Stanley advised Sanofi, which used Weil, Gotshal & Manges as its law firm. Synthorx’s advisers were Centerview Partners LLC and Cooley LLP.

More must-read stories from Fortune:

—Want a SIM card in China? You’ll now need to get your face scanned first
—2020 Crystal Ball: Predictions for the economy, politics, technology, and more
—In the wake of Brexit, Amsterdam is the new London
—The world’s third-richest man has a Donald Trump problem
—Why it’s still so hard to sell medical marijuana in Asia
Catch up with Data Sheet, Fortune’s daily digest on the business of tech.

About the Authors
By James Paton
See full bioRight Arrow Button Icon
By Bloomberg
See full bioRight Arrow Button Icon
0

Most Popular

placeholder alt text
Economy
Tariffs are taxes and they were used to finance the federal government until the 1913 income tax. A top economist breaks it down
By Kent JonesDecember 12, 2025
1 day ago
placeholder alt text
Success
Apple cofounder Ronald Wayne sold his 10% stake for $800 in 1976—today it’d be worth up to $400 billion
By Preston ForeDecember 12, 2025
1 day ago
placeholder alt text
Success
40% of Stanford undergrads receive disability accommodations—but it’s become a college-wide phenomenon as Gen Z try to succeed in the current climate
By Preston ForeDecember 12, 2025
1 day ago
placeholder alt text
Economy
The Fed just ‘Trump-proofed’ itself with a unanimous move to preempt a potential leadership shake-up
By Jason MaDecember 12, 2025
22 hours ago
placeholder alt text
Economy
For the first time since Trump’s tariff rollout, import tax revenue has fallen, threatening his lofty plans to slash the $38 trillion national debt
By Sasha RogelbergDecember 12, 2025
1 day ago
placeholder alt text
Success
Apple CEO Tim Cook out-earns the average American’s salary in just 7 hours—to put that into context, he could buy a new $439,000 home in just 2 days
By Emma BurleighDecember 12, 2025
1 day ago
Rankings
  • 100 Best Companies
  • Fortune 500
  • Global 500
  • Fortune 500 Europe
  • Most Powerful Women
  • Future 50
  • World’s Most Admired Companies
  • See All Rankings
Sections
  • Finance
  • Leadership
  • Success
  • Tech
  • Asia
  • Europe
  • Environment
  • Fortune Crypto
  • Health
  • Retail
  • Lifestyle
  • Politics
  • Newsletters
  • Magazine
  • Features
  • Commentary
  • Mpw
  • CEO Initiative
  • Conferences
  • Personal Finance
  • Education
Customer Support
  • Frequently Asked Questions
  • Customer Service Portal
  • Privacy Policy
  • Terms Of Use
  • Single Issues For Purchase
  • International Print
Commercial Services
  • Advertising
  • Fortune Brand Studio
  • Fortune Analytics
  • Fortune Conferences
  • Business Development
About Us
  • About Us
  • Editorial Calendar
  • Press Center
  • Work At Fortune
  • Diversity And Inclusion
  • Terms And Conditions
  • Site Map

© 2025 Fortune Media IP Limited. All Rights Reserved. Use of this site constitutes acceptance of our Terms of Use and Privacy Policy | CA Notice at Collection and Privacy Notice | Do Not Sell/Share My Personal Information
FORTUNE is a trademark of Fortune Media IP Limited, registered in the U.S. and other countries. FORTUNE may receive compensation for some links to products and services on this website. Offers may be subject to change without notice.