Novartis\' $12B del-desiran flops in crucial phase 3 trial
Money MovesHarbor trial miss casts doubt on Avidity acquisition as patent expiries loom
Today: Harbor trial flops for del-desiranNew here? Follow stories to track developments over time. Create a free account to get updates when stories you care about change.
Overview
Updated 2 hours agoNovartis' experimental muscle-disease drug del-desiran failed its phase 3 Harbor trial, missing the primary endpoint and sending shares down. The drug was the centerpiece of the company's $12 billion acquisition of Avidity Biosciences, which closed last year.
The miss asts doubt on Novartis' pipeline strategy just when its older blockbusters face patent expiries. It also deals a blow to the broader class of RNA-based therapies;del-desiran was meant to prove the platform's worth.
Why it matters
The failure puts Novartis' $12 billion bet in question, threatening its plan to replace revenue from older drugs losing patent protection.
Questions about this story
Free account needed to ask — your question is kept and asked for you right after sign-up. Answers are public.
No questions yet — be the first to ask.
Key Indicators
Voices
Curated perspectives — historical figures and your fellow readers.
Play
Exploring all sides of a story is often best achieved with Play.
WHO SAID WHAT?
Can you match the quotes to the right people?
- points for each correct match.
- time bonus when you answer in under seconds.
- streak bonus once you hit correct in a row.
— Who said this?
Tip: press 1– to answer.
points — sign up to put that on the leaderboard.
Higher or Lower
A number from this story, against one from elsewhere in the news — guess which is bigger, then keep the chain going. 5 rounds, 3 strikes; a miss costs a strike and resets your streak.
Keyboard: ↓/L lower · ↑/H higher
0 points — sign up to put that on the leaderboard.
Connections
Sixteen names from the news. Find the four hidden groups of four. Four mistakes max.
Sign up to keep a daily streak — a new puzzle lands every day.
Exit debate?
Your progress in this debate will be lost.
- 1 Two AI personas square off on this story.
- 2 You predict who'll win each round — correct picks earn XP.
- 3 One crossfire question is yours to fire. Pick it carefully.
Couldn't generate a topic
Select Your Champions
Choose one persona for each side of the debate
DEBATE TOPIC
Choose personas with different perspectives for a more dynamic debate.
Select debater for this side:
No debate personas available right now.
Select debater for this side:
No debate personas available right now.
Who's Got This Round?
Make your prediction before the referee scores
The referee scores both sides on
Round Results
Set the Crossfire
Pick the question both personas must answer in the final round
Debate Oracle! You called every round!
Sharp Instincts! You know your debaters!
The Coin Flip Strategist! Perfectly balanced!
The Contrarian! Bold predictions!
Inverse Genius! Try betting the opposite next time!
XP Breakdown
Prediction History
People Involved
Organizations Involved
Swiss drugmaker that spent $12 billion to acquire Avidity Biosciences.
Developer of antibody-oligonucleotide conjugates, a platform for delivering RNA therapeutics.
Timeline
August 2024 September 2026
-
Harbor trial flops for del-desiran
Today Clinical TrialDel-desiran failed its phase 3 Harbor trial, missing the primary endpoint and dealing a major blow to Novartis' Avidity acquisition.
-
Pelacarsen fails phase 3 Lp(a) trial
Clinical TrialNovartis' cholesterol drug pelacarsen missed its primary endpoint, a separate setback for the pipeline.
-
Novartis bets $12B on Avidity
AcquisitionNovartis agreed to buy Avidity Biosciences, whose RNA platform includes del-desiran, arare-muscle-disease therapy.
Historical Context
2 moments from history that rhyme with this story — and how they unfolded.
Novartis/AveXis Zolgensma (2018-2019)
Novartis paid $8.7 billion for AveXis, whose gene therapy Zolgensma treated spinal muscular atrophy. The drug won FDA approval with strong efficacy data, becoming one of the most expensive drugs ever sold.
Zolgensma generated billions in revenue and validated Novartis' rare-disease M&A strategy.
It set a precedent that big bets on muscle-disease gene therapies could pay off,numazzicando later deals like Avidity.
The AveXis success is why investors hoped del-desiran could repeat that magic;the Harbor failure now breaks that pattern, making the $12B Avidity purchase look far riskier.
Astellas/Audentes Therapeutics (2019-2020)
Astellas paid $3 billion for Audentes, betting on its gene therapy for a rare muscle disease. In clinical hold issued in early 2020 after a patient died of liver toxicity, and the program never recovered.
Astellas halted the trial, took awritedown, andabandoned the program.
The failure chilled investor enthusiasm for high-priced rare-disease acquisitions.
Like Astellas, Novartis paid a premium for arsingle-platform bet in rare muscle disease;the clinical failure now threatens to erase most of that value.
