Gilead Strikes Again: $415M Bet on ADCs with Tubulis Deal

Gilead Sciences, Inc. (Nasdaq: GILD) and Tubulis entered an exclusive option and license agreement to develop an antibody-drug conjugate (ADC) targeting a solid tumor. The agreement grants Gilead access to Tubulis’ proprietary Tubutecan and Alco5 platforms. Both companies will collaborate to identify the optimal technology for development. Tubulis will lead discovery and development efforts to create a Topoisomerase I inhibitor-based ADC candidate with enhanced biophysical properties and stability.

Deal Includes $20M Upfront, $30M Option Fee, and Up to $415M in Milestone Payments

Gilead Sciences on Tuesday announced a $20 million upfront payment as part of an exclusive option and license agreement with Tubulis to advance innovative ADC therapies for solid tumors. The deal positions Gilead to strengthen its presence in the ADC space following setbacks, including the withdrawal of Trodelvy in bladder cancer and a late-stage trial failure in NSCLC.

In addition to the initial payment, Gilead will pay a $30 million option exercise fee if it chooses to exclusively license the program. The agreement also includes development and commercialization milestone payments, bringing the total potential value to $415 million. Tubulis is also eligible for tiered royalties ranging from mid-single to low-double digits on any marketed product.

If Gilead exercises its licensing option, it will take over full responsibility for the development and commercialization of the ADC program. Tubulis, however, will focus on leveraging its proprietary Tubutecan and Alco5 platforms during the discovery phase to address challenges such as durability and off-target toxicity.

Flavius Martin, MD, Executive Vice President of Research at Gilead, highlighted the importance of the partnership, stating, “This collaboration allows us to access novel technologies critical to advancing our pipeline. Together with Tubulis, we aim to unlock the full therapeutic potential of the ADC modality and deliver next-generation treatments that address significant care gaps.”

Targeting Precision with Topo-I Payloads to Minimize Toxicity and Maximize Impact

The partnership focuses on using Tubulis’ own Tubutecan platform, built with P5 conjugation technology, to develop ultra-stable ADCs. These ADCs are designed to deliver topoisomerase-I payloads directly to their targets while reducing unwanted toxicities, as outlined on Tubulis’ website.

In April 2023, Bristol Myers Squibb recognized the potential of Tubulis’ platform and paid $22.75 million upfront, with the total deal exceeding $1 billion. BMS also plans to use Tubutecan to develop safer and more effective ADCs targeting solid tumors, aligning with Gilead’s current focus.

In March 2024, Tubulis secured nearly $140 million in a Series B2 funding round to support its pipeline of ADC candidates. This funding will help advance TUB-040, aimed at ovarian and lung cancers, and TUB-030, which targets solid tumors.

For Gilead, this agreement marks a renewed focus on ADCs following recent challenges. In October 2024, the company withdrew Trodelvy from the bladder cancer market after the Phase III TROPiCS-04 trial failed to show significant overall survival benefits. Similarly, in January 2024, the Phase III EVOKE-01 trial in non-small cell lung cancer showed no significant improvement in overall survival compared to docetaxel. These setbacks make the Tubulis partnership a critical step in revitalizing Gilead’s ADC efforts.

Author

Bernice Lottering