Most next-generation ADC companies you read about have one asset in the clinic and a deck full of promises about what’s coming next.
Whitehawk Therapeutics has two. And it’s about to file an IND on a third.
At AACR 2026 this weekend, the Morristown-based biotech laid out its full preclinical case for the Carbon Bridge Cysteine Re-pairing platform, the conjugation chemistry sitting under all three of its candidates. The pitch is familiar to anyone following the ADC space: better therapeutic index, less free-payload exposure, more stable in plasma. What’s less familiar is the pace.
HWK-007, targeting PTK7, is already in Phase 1 for non-squamous EGFR wild-type NSCLC, platinum-resistant ovarian, and endometrial. HWK-016, targeting MUC16, is in Phase 1 for advanced ovarian and endometrial. Both use a TOP1 inhibitor payload. Both are running in parallel.
Now comes HWK-206, a biparatopic SEZ6 ADC, IND filing planned for mid-2026, Phase 1 initiation targeted for Q3.
The Biotech Voyager
Early-stage biotech signals, personalized.
The signals that matter to you, contextualized and written directly to you, so you cut through the noise and immediately understand why it matters.
SEZ6 is a target with a real comp. AbbVie has been chasing it with ABBV-706 in small cell lung cancer, and a biparatopic angle, which binds two different epitopes on the same target, is the kind of differentiation you pitch when the frontrunner has already set the bar on potency. Whitehawk hasn’t disclosed indication yet, but SCLC is where SEZ6 lives.
The platform is doing real work here. TOP1 inhibitor ADCs have a known problem: the payload leaks into circulation, the therapeutic window shrinks, and dose-limiting toxicities show up before you get the exposure you want in the tumor. Carbon Bridge is Whitehawk’s answer to that, and the AACR data focused on plasma stability and low free-payload exposure in non-human primates. No response numbers yet. Those come once HWK-007 and HWK-016 read out.
What makes this worth watching is pipeline depth at a moment when the ADC space is thinning out. Lilly bought CrossBridge Bio’s dual-payload platform before it hit the clinic. ABION’s approach has been getting attention for doing the opposite of most ADC companies. Everyone is differentiating in a different direction, and the ones that last are the ones with more than one shot on goal.
Whitehawk has three shots queued up, all on the same platform, all with TOP1 payloads. If HWK-007 or HWK-016 reads out cleanly next year, the SEZ6 asset becomes the third validation of a platform rather than a preclinical curiosity.
That’s a different pitch than most of the field is making right now.
