UPDATE: Larimar (LRMR) A Smart Money Showdown – RA Capital Bails

What happened: On February 17, premier biotech hedge fund RA Capital Management filed a Schedule 13G indicating they have completely exited their position in Larimar Therapeutics (holding 0 shares as of December 31, 2025).

The Plain English Translation: We officially have a heavyweight battle on our hands. Last month (linked in commments), I noted that Blue Owl Healthcare was aggressively maneuvering to maintain a massive position in LRMR. Now, we see that Peter Kolchinsky’s RA Capital — arguably one of the sharpest biotech funds on Wall Street — took the exact opposite side of the trade and dumped their entire position before the new year.

Why it matters: RA Capital employs a deep bench of scientists to evaluate clinical data. Their exit suggests they may have looked at the anaphylaxis risk (the 10-18% allergic reaction rate I discussed in my main thesis) and decided that the new "start low, go slow" titration protocol isn't necessarily worth betting the house on. They chose to de-risk completely rather than hold through the upcoming Q1 2026 open-label safety update.

Impact on Thesis: HOLD / WATCH LIST (Conviction Maintained). This conflicting institutional activity supports the core thesis: Do not play the guessing game. When the smartest guys in the room are taking completely opposite bets on the same drug, retail investors have no business gambling on the outcome. Consider staying on the sidelines and wait for the actual Q1 clinical receipts to prove whether the safety fix actually works.