Sutro puts lead ADC on hold, cuts staff and changes CEO
Jane Chung has replaced Bill Newell as Sutro's CEO.
Antibody-drug conjugate (ADC) specialist Sutro Biopharma has shelved its lead drug for ovarian cancer and turned its attention to a trio of "next-generation" drugs still in preclinical development.
The dramatic decision – which has been accompanied by the laying off of around half its workforce and a change in chief executive – comes after Sutro revealed positive results from a phase 2/3 trial of lead drug luveltamab tazevibulin (luvelta, also known as STRO-002) in platinum-resistant ovarian cancer in December.
Sutro said at the time that the 32% objective response rate (ORR) in the dose-finding stage of the REFRαME-O1 study had set up the second pivotal stage of the trial, and it was hoping to file for accelerated approval of the folate receptor α-targeting ADC in mid-2027.
Just a few months later, luvelta has been "deprioritised" while Sutro looks for a partner to take the programme forward, and it is focusing its efforts on a new crop of ADCs that either use a different chemotherapeutic payload (exatecan) – the drug-killing component of the molecule – or dual payloads.
Jane Chung, president and chief operating officer at Sutro, is replacing Bill Newell as chief executive as the company starts the process of shedding staff and shutting down a GMP-compliant manufacturing facility for luvelta.
In a statement, the company said it is stopping luvelta's clinical development "across all indications." It has also been investigating the drug's activity in other trials involving patients with non-small cell lung cancer (NSCLC), a form of acute myeloid leukaemia (AML), and other solid tumours.
The stripped-down company's new internal pipeline will be headed by STRO-004, an exatecan-bearing ADC target tissue factor (TF), which is expected to enter the clinic in the second half of 2025.
The other two preclinical candidates are STRO-006, an integrin beta-6 ADC due to start trials in 2026, and an as-yet unidentified dual-payload ADC, which is slated to enter the clinic in 2027.
South San Francisco-based Sutro ended last year with almost $317 million in cash, and reckons that the cutbacks will allow that to keep it going into the fourth quarter of 2026. It could also be in line for milestone payments from partnered programmes during that period.
It has collaborations in place with Vaxcyte on a pair of pneumococcal vaccine candidates, with Ipsen on a ROR1-directed ADC for solid tumours and blood cancers, and with Astellas on various undisclosed oncology programmes.
