One antibody infusion vs. valacyclovir: mixed results from MATCH‑2

Monoclonal antibodies are lab-made versions of the proteins our immune system uses to tag invaders. HDIT101, developed by Heidelberg ImmunoTherapeutics in Germany, binds glycoprotein B, a protein both HSV‑1 and HSV‑2 need to enter cells. MATCH‑2, published in Pharmacological Research, was its first trial in people with genital herpes.

How the trial worked

• Adults with chronic recurrent genital HSV‑2 (at least four outbreaks in the previous year) were enrolled at eight sites in Germany.
• 122 participants were randomized 2:1 to a single intravenous infusion of HDIT101 or to standard episodic valacyclovir (500 mg twice a day for three days at each outbreak). Matching placebos meant no one knew which treatment they received.
• Participants were followed for 180 days.

What they found

• Safety: HDIT101 was well tolerated.
• Main goal: the share of days with lesions was almost identical, about 15% in both groups, so HDIT101 was not superior on the primary endpoint.
• Secondary results: people given HDIT101 went somewhat longer before their first recurrence (median 47 vs 39 days, not statistically significant) and had fewer recurrences on average (2.7 vs 3.8 in the per-protocol analysis).

What to keep in mind

A trial that misses its primary endpoint is not a success, even with encouraging secondary signals, and the recurrence finding needs to be confirmed in a new trial designed to test it. Still, a treatment that works from a single infusion instead of daily pills would be a meaningful option, which is why this result is worth following.