Novartis Spent $12 Billion on a Bet. The Bet Just Lost.

The strategic logic was compelling on paper. Novartis was buying not just one drug, but an entire platform for delivering RNA therapies to muscle. The company's own projections suggested the Avidity portfolio could bump its 2024–2029 sales growth rate from 5% to 6% annually. Analysts at Vontobel had modeled del-desiran alone reaching $3 billion in peak annual sales.

That $3 billion assumption? Vontobel just removed it from their model entirely. Analyst Stefan Schneider said the result "further weakened confidence" in the other therapies Novartis gained through the deal. Vontobel cut its Novartis price target from 128 to 125 Swiss francs and kept a hold rating.

Guggenheim Securities had previously warned that del-desiran's success was "crucial" for validating the entire Avidity acquisition. That word, "crucial," looks prophetic now.

The Bigger Problem: Novartis's M&A Report Card

This isn't happening in a vacuum. Novartis has been on an acquisition spree, building its pipeline through deals the way a fantasy football manager builds a roster through trades. Since 2023, the company has picked up Chinook Therapeutics (about $3.5 billion), MorphoSys (roughly €2.7 billion), Anthos Therapeutics (up to $3.1 billion), and several smaller bolt-ons.

CEO Vas Narasimhan has been consistent about the strategy: target assets that can launch within five years, with a preference for deals under $2 billion. The Avidity acquisition was the glaring exception, a supersized bet on a platform rather than a single product.

Bloomberg Intelligence noted that the HARBOR failure now adds pressure on Narasimhan to clarify growth expectations at the company's November investor meeting. Analysts are also questioning whether Novartis's deal-making quality can hold up as the company faces what Bloomberg described as the biggest patent cliff in its history.

When your largest acquisition stumbles this quickly, every future deal gets scrutinized more harshly. That's the hidden cost here.

Not Everything Is Dead

Before we write the obituary for Avidity's platform, some context is important. Del-desiran was the flagship, but it wasn't the only ship in the fleet.

Avidity's FSHD program (del-brax) actually delivered good news recently. In June 2026, the FORTITUDE Phase 1/2 study met its primary and key secondary biomarker endpoints, showing meaningful reductions in disease-related biomarkers. FSHD is facioscapulohumeral dystrophy, another rare muscle disease, and this data suggests the AOC delivery platform itself still works. The problem with del-desiran may have been specific to the drug or the DM1 indication rather than a fundamental flaw in the technology.

There's also del-zota, Avidity's Duchenne muscular dystrophy program, which had been tracking toward a potential regulatory filing. Whether Novartis still pursues that timeline aggressively remains to be seen.

The Race Isn't Over

Novartis isn't the only company chasing muscle-targeted RNA therapies. Dyne Therapeutics has its own Phase 3 trial (called HARMONIA) running in DM1 with roughly 150 patients, using a different muscle-targeting approach. Sarepta Therapeutics is earlier in the game, testing peptide-conjugated RNA drugs in both DM1 and FSHD, with first-in-human data showing about a 50% reduction in the problematic DMPK RNA in early studies.

Del-desiran's failure doesn't mean DM1 is untreatable. It means the first serious attempt at a pivotal trial in muscle-targeted RNA came up short. Competitors will study the HARBOR results carefully, trying to understand whether the endpoint was wrong, the drug was insufficient, or the disease is harder to move than anyone thought.

What Happens Next

Novartis now faces an uncomfortable stretch. The company needs to decide how aggressively to invest in Avidity's remaining programs while restoring investor confidence that was already fragile. The del-brax FSHD data provides some cover, but "our $12 billion deal still has a Phase 1/2 program that hit biomarker endpoints" is a tough sell to shareholders who were expecting a blockbuster.

The November investor meeting will be the real test. Narasimhan will need to articulate a growth story that doesn't lean so heavily on acquired pipelines that haven't yet proven themselves in pivotal trials. And he'll need to do it while every analyst in the room is doing mental math on the Avidity write-down that may or may not be coming.

For the broader RNA muscle-targeting field, the stakes are just as high. If the delivery technology works (and the del-brax data suggests it can), then this failure is a setback, not an ending. But if it turns out that getting RNA drugs to muscle is easier in theory than in practice, a lot of expensive bets across the industry just got riskier.

Twelve billion dollars buys a lot of things. Certainty, apparently, isn't one of them.