Havah’s Implant Aims to Bend Cancer to Medicine’s Will

BOULDER, CO – February 19, 2026 – A Boulder-based biopharmaceutical company is poised to unveil what it believes is a paradigm shift in the fight against breast cancer. Havah Therapeutics will present groundbreaking details on its lead candidate, HAV-088, at a major conference this week, outlining a novel strategy that aims to outmaneuver hormone-sensitive tumors by activating, rather than blocking, key cellular pathways.

The presentation, to be delivered by Professor Stephen Birrell at the RiseUp for Breast Cancer and Women’s Health Conference in San Francisco, is provocatively titled “HAV-088: Bending Evolution to the Will of Medicine.” It promises to detail a new approach for treating hormone receptor-positive (HR+) breast cancer, the most common form of the disease, which could offer a more effective and tolerable option for thousands of patients.

A New Weapon in the Hormonal Arsenal

For decades, the cornerstone of treating HR+ breast cancer has been to starve the tumor of estrogen, its primary fuel. Therapies like tamoxifen, which blocks estrogen receptors, and aromatase inhibitors (AIs), which halt estrogen production, have saved countless lives. However, these treatments can come with significant side effects and tumors can eventually develop resistance, leaving patients with fewer options.

Havah Therapeutics is pioneering a fundamentally different approach. Instead of focusing on the estrogen receptor (ER), its lead candidate, HAV-088, targets the androgen receptor (AR). Androgens, often considered male hormones like testosterone, are present in women and play a complex role in breast tissue. Research has shown that in the majority of HR+ breast cancers, activating the AR can have a powerful anti-proliferative effect, effectively acting as a brake on the estrogen-driven engine of cancer growth.

HAV-088 is a first-in-class AR agonist—a molecule designed to activate the receptor. This activation is believed to suppress ER signaling, essentially hijacking the tumor’s internal wiring to shut down its growth programs. This concept, which the company calls “endocrine steering,” marks a significant departure from simply cutting off the fuel supply. It’s a more nuanced strategy of manipulating the hormonal environment to the patient's advantage.

The therapy itself is also innovative. HAV-088 is delivered via a small subcutaneous implant that provides three months of continuous, steady-state therapy. The implant contains a combination of testosterone to activate the AR and a low dose of the aromatase inhibitor anastrozole. This dual-action formulation is designed to maximize the anti-tumor effect of AR activation while preventing the testosterone from being converted into estrogen, a historical concern with older androgen-based therapies.

Targeting Unmet Needs and Improving Patient Lives

Beyond its novel mechanism, HAV-088 is being developed to address specific and challenging clinical scenarios where new options are desperately needed. The company is currently enrolling patients in two key studies that highlight this patient-centric focus.

One is a pilot randomized controlled trial directly comparing HAV-088 to the current standard, tamoxifen. The study focuses on a particularly vulnerable group: high-risk premenopausal women who have dense breasts and show marked background parenchymal enhancement (BPE) on MRI scans. These factors are associated with an increased risk of developing breast cancer, and effective, well-tolerated preventative strategies are a major unmet need.

The second, a Phase 2 study named RECAST DCIS, is evaluating HAV-088 as a non-surgical treatment for ductal carcinoma in situ. DCIS, often called stage 0 breast cancer, involves abnormal cells confined to a milk duct. While not life-threatening on its own, it can progress to invasive cancer. Standard treatment often involves surgery, sometimes followed by radiation and years of tamoxifen. A safe and effective non-surgical option could spare thousands of women from invasive procedures and their associated physical and psychological tolls.

The three-month implant delivery system is a cornerstone of the therapy’s potential to improve quality of life. Forgetting to take a daily pill is a common issue that can compromise the effectiveness of long-term cancer therapies. The implant removes this burden, ensuring consistent drug delivery and potentially improving clinical outcomes. Furthermore, by creating a more stable hormonal environment, Havah hopes to mitigate some of the debilitating side effects—such as severe hot flashes, joint pain, and bone density loss—that often lead patients to discontinue traditional endocrine therapies.

Clinical Validation and Market Disruption

The upcoming presentation by Professor Birrell, Havah’s Founder and Chair of its Clinical Advisory Board, is a critical step in validating this new therapeutic class. Presenting at a prominent conference like RiseUp provides a platform to share data with leading oncologists, researchers, and industry experts, building the scientific consensus needed to move the field forward. The presentation is expected to provide an overview of the trial comparing HAV-088 to tamoxifen and detail an integrated evidence chain linking drug exposure to changes in tissue biology and advanced imaging biomarkers.

In a multi-billion dollar oncology market dominated by estrogen-blockers and chemotherapy, a successful AR agonist could be a significant disruptor. While other companies are exploring AR-targeted therapies, most are focused on AR antagonists for different cancer subtypes, such as triple-negative breast cancer. Havah’s focus on AR agonism for the much larger HR+ breast cancer population places it in a unique competitive position.

If Havah's clinical trials demonstrate that HAV-088 is not only effective but also offers a superior safety profile and better quality of life, it could carve out a substantial portion of the market, initially for specific high-risk populations and potentially as a broader alternative to existing treatments. The company's recent filing of a provisional patent for HAV-088 in treating DCIS signals a clear strategy to protect its innovation and establish a strong foothold in both preventative medicine and active cancer treatment.

As the medical community gathers in San Francisco, all eyes will be on Havah Therapeutics to see if its bold approach to "bending evolution" can deliver a new, more hopeful chapter for patients with breast cancer. The data and framework presented this week will offer the first public glimpse into a therapy that could redefine hormonal treatment for the next generation.