Why Alnylam Pharmaceuticals (ALNY) Stock Is Down Today

Alnylam Pharmaceuticals (ALNY) is down 3.8% today. Here is some analysis on what might have caused this price movement.

Analysis: The most likely driver is continued pressure on sentiment around Alnylam’s ATTR-cardiomyopathy franchise after full late-August conference data from a rival transthyretin gene-silencing study failed to show a significant benefit on its primary endpoint. The pullback may also reflect lingering caution after Alnylam cut its 2026 TTR sales outlook in late July, while there does not appear to be a fresh major company-specific negative announcement today.

Details:

A rival Phase 3 ATTR-CM study for eplontersen did not meet its primary efficacy endpoint, keeping investor focus on whether gene-silencing therapies can consistently deliver strong cardiovascular outcomes in this market.

Alnylam’s own second-quarter update lowered full-year 2026 TTR product revenue guidance after the company said early launch demand patterns for AMVUTTRA were normalizing in the U.S. second-line setting.

Alnylam has recently highlighted supportive AMVUTTRA data and upcoming investor presentations, but those updates were not an obvious new positive catalyst for shares on today’s session.

With no clear new filing or earnings release tied to today, the stock move looks consistent with biotech investors reassessing the commercial and competitive outlook for Alnylam’s TTR business.

Sources:

Alnylam investor relations, AstraZeneca, Benzinga

Disclaimer: This price movement analysis was generated with the help of AI. Please double-check the information provided for mistakes.

$ALNY Insider Trading Activity

$ALNY insiders have traded $ALNY stock on the open market 19 times in the past 6 months. Of those trades, 0 have been purchases and 19 have been sales.

Here’s a breakdown of recent trading of $ALNY stock by insiders over the last 6 months:

MELISSA MCLAUGHLIN (Chief Human Resources Officer) has made 0 purchases and 14 sales selling 3,910 shares for an estimated $1,274,342.
DAVID E I PYOTT has made 0 purchases and 5 sales selling 3,830 shares for an estimated $1,145,852.

To track insider transactions, check out Quiver Quantitative's insider trading dashboard. You can access data on insider stock transactions through the Quiver Quantitative API insider transaction endpoint.

EARLY ACCESS

Receive ALNY Data Alerts

Real-time alerts on filings, insider trades, and market signals — before everyone else.

Get Alerts →

$ALNY Hedge Fund Activity

We have seen 418 institutional investors add shares of $ALNY stock to their portfolio, and 478 decrease their positions in their most recent quarter.

Here are some of the largest recent moves:

T. ROWE PRICE INVESTMENT MANAGEMENT, INC. added 4,490,826 shares (+390.0%) to their portfolio in Q2 2026, for an estimated $1,351,873,350
JPMORGAN CHASE & CO added 2,675,517 shares (+inf%) to their portfolio in Q2 2026, for an estimated $805,410,882
INVESCO LTD. added 2,462,592 shares (+190.6%) to their portfolio in Q2 2026, for an estimated $741,314,069
MARSHALL WACE, LLP removed 839,519 shares (-76.4%) from their portfolio in Q2 2026, for an estimated $252,720,404
DEEP TRACK CAPITAL, LP added 825,000 shares (+inf%) to their portfolio in Q2 2026, for an estimated $248,349,749
SIXTH STREET PARTNERS MANAGEMENT COMPANY, L.P. added 755,377 shares (+inf%) to their portfolio in Q2 2026, for an estimated $227,391,138
D. E. SHAW & CO., INC. added 659,616 shares (+148.4%) to their portfolio in Q2 2026, for an estimated $198,564,204

To track hedge funds' stock portfolios, check out Quiver Quantitative's institutional holdings dashboard. You can access data on hedge funds moves and 13F filings through the Quiver Quantitative API 13F endpoint.

$ALNY Analyst Ratings

Wall Street analysts have issued reports on $ALNY in the last several months. We have seen 1 firms issue buy ratings on the stock, and 0 firms issue sell ratings.

Here are some recent analyst ratings:

HC Wainwright & Co. issued a "Buy" rating on 06/29/2026

To track analyst ratings and price targets for $ALNY, check out Quiver Quantitative's $ALNY forecast page.

$ALNY Price Targets

Multiple analysts have issued price targets for $ALNY recently. We have seen 7 analysts offer price targets for $ALNY in the last 6 months, with a median target of $425.0.

Here are some recent targets:

Patrick R. Trucchio from HC Wainwright & Co. set a target price of $470.0 on 06/29/2026
Eric Joseph from Citigroup set a target price of $380.0 on 05/19/2026
Derek Archila from Wells Fargo set a target price of $377.0 on 05/01/2026
Luca Issi from RBC Capital set a target price of $445.0 on 05/01/2026
Danielle Brill from Truist Securities set a target price of $505.0 on 04/13/2026
Keay Nakae from Chardan Capital set a target price of $425.0 on 03/25/2026
Faisal Khurshid from Jefferies set a target price of $330.0 on 03/16/2026

This article is not financial advice. See Quiver Quantitative's disclaimers for more information. Note that there may be inaccuracies due to mistakes in ticker-mapping, and other anomalies.