Terremoto Biosciences Receives FDA Fast Track Designation for TER-2013 in Advanced HR+/HER2- Breast Cancer
Terremoto Biosciences, a biotechnology company focused on developing highly targeted small-molecule therapies for cancer, has announced that the U.S. Food and Drug Administration (FDA) has granted Fast Track Designation to its lead investigational drug, TER-2013. The designation applies to the therapy’s development in patients with locally advanced, unresectable, or metastatic hormone receptor-positive, HER2-negative (HR+/HER2-) breast cancer whose tumors harbor alterations in the AKT/PI3K/PTEN signaling pathway and whose disease has progressed following prior endocrine-based therapy and treatment with a CDK4/6 inhibitor.
The regulatory milestone marks an important step forward for TER-2013, a highly selective AKT1 inhibitor designed to address a genetically defined subset of breast cancer patients with limited treatment options after standard therapies fail. The Fast Track designation is intended to accelerate the development and regulatory review of therapies that treat serious conditions and address unmet medical needs.
Accelerating Development for High-Unmet-Need Breast Cancer Patients
HR+/HER2- breast cancer is the most common subtype of breast cancer, and while many patients benefit from endocrine therapy and CDK4/6 inhibitors in earlier lines of treatment, resistance eventually develops in a significant proportion of cases. Once the disease progresses after these standard therapies, treatment options become more limited, particularly for patients whose tumors exhibit alterations in the AKT/PI3K/PTEN pathway.
These genetic alterations are known to drive tumor growth and contribute to treatment resistance, making them an important target for next-generation therapies. However, effective and well-tolerated targeted treatments for this specific molecular population remain an area of significant unmet medical need.
By receiving Fast Track Designation, TER-2013 gains access to a range of regulatory advantages intended to streamline its development pathway. These include more frequent interactions with the FDA, opportunities for earlier discussions on clinical trial design and data requirements, and potential eligibility for accelerated approval or priority review, provided the drug meets the necessary criteria during development.
The designation underscores the FDA’s recognition of both the seriousness of advanced HR+/HER2- breast cancer and the need for innovative therapies that can improve outcomes in patients whose disease has progressed on existing standard-of-care treatments.
Company Perspective on the Regulatory Milestone
Charles Baum, M.D., Ph.D., Chief Executive Officer of Terremoto Biosciences, emphasized the significance of the designation in the context of ongoing unmet clinical needs in advanced breast cancer.
He noted that the recognition from the FDA reinforces the importance of developing more effective and selective treatment options for patients with difficult-to-treat cancers. According to Baum, the company remains focused on advancing highly selective therapeutic candidates designed to expand the available treatment landscape for patients who have exhausted current standard therapies.
The Fast Track designation also validates the company’s broader strategy of targeting genetically defined cancer populations with precision medicines designed to improve efficacy while minimizing off-target effects.
A Highly Selective Approach to AKT1 Inhibition
TER-2013 is an orally administered small-molecule inhibitor specifically designed to target the AKT1 isoform, a key component of the PI3K/AKT signaling pathway that plays a central role in regulating cell growth, survival, and metabolism.
Dysregulation of the PI3K/AKT/PTEN pathway is one of the most frequently observed molecular abnormalities in cancer, including breast cancer. Within this pathway, AKT exists in multiple isoforms—AKT1, AKT2, and AKT3—which have distinct biological functions. While inhibition of the pathway as a whole has been explored in prior drug development efforts, earlier pan-AKT inhibitors have often been limited by toxicity and insufficient therapeutic selectivity.
TER-2013 was designed to overcome these challenges by selectively targeting AKT1 while sparing AKT2 and AKT3, as well as minimizing activity against unrelated proteins. This selective approach is intended to maintain strong anti-tumor activity while reducing the off-target toxicities that have historically limited broader AKT inhibition strategies.
James Christensen, Ph.D., President and Head of Research and Development at Terremoto Biosciences, explained that preclinical data demonstrated potent and sustained inhibition of AKT1, supporting the scientific rationale behind the molecule’s design.
He highlighted that the program was specifically engineered to address limitations seen with earlier pan-AKT inhibitors, which often affected multiple isoforms and led to undesirable side effects. By focusing on AKT1 selectivity, TER-2013 aims to maximize therapeutic impact on tumor-driving biology while minimizing disruption to normal physiological processes regulated by other AKT isoforms.
Clinical Development Progress
TER-2013 is currently being evaluated in a Phase 1 clinical trial (NCT07109726) involving patients with advanced solid tumors that harbor alterations in the AKT/PI3K/PTEN signaling pathway. The study is designed to assess the safety, tolerability, pharmacokinetics, and early signs of anti-tumor activity of the investigational therapy.
The Phase 1 trial includes a dose-escalation portion, which has already been completed. This phase is intended to identify appropriate dosing levels and evaluate initial safety profiles across different dose ranges. Based on the findings from this stage, the company is now working toward selecting an optimal dose for proof-of-concept expansion cohorts.
These expansion studies will focus on patients whose tumors carry AKT/PI3K/PTEN pathway alterations, including those with HR+/HER2- breast cancer, as well as potentially other solid tumor types that share similar molecular drivers.
In addition to the planned expansion in breast cancer, Terremoto Biosciences has indicated that it is also exploring opportunities to evaluate TER-2013 in additional patient populations. These future studies may help broaden the therapeutic potential of the drug beyond its initial indication.
Addressing a Genetically Defined Patient Population
The development of TER-2013 reflects a broader trend in oncology toward precision medicine, where therapies are tailored to specific genetic alterations that drive tumor growth. In the case of HR+/HER2- breast cancer, mutations or alterations in the AKT/PI3K/PTEN pathway are associated with disease progression and resistance to endocrine therapies and CDK4/6 inhibitors.
By directly targeting AKT1, TER-2013 is designed to intervene in a key signaling node within this pathway, potentially offering a more effective approach for patients whose tumors rely on this mechanism for survival and proliferation.
This targeted strategy is particularly relevant for patients whose disease has progressed after standard treatment options, a setting in which new therapeutic approaches are urgently needed. As resistance mechanisms become more complex, precision-targeted therapies like TER-2013 are increasingly viewed as a promising path forward in oncology drug development.
Importance of Fast Track Designation
The FDA’s Fast Track Designation is granted to therapies that show potential to address serious conditions and fill unmet medical needs. For drug developers, the designation provides several advantages that can help accelerate clinical development timelines.
These benefits include more frequent communication with the FDA, eligibility for rolling review of regulatory submissions, and potential access to accelerated approval pathways if early clinical evidence supports efficacy. In some cases, drugs that meet the criteria may also qualify for priority review, which shortens the FDA’s standard review timeline once a marketing application is submitted.
For TER-2013, this designation may help streamline development efforts as the company advances from early-stage clinical testing toward later-stage studies in defined patient populations.
As Terremoto Biosciences continues to advance TER-2013 through clinical development, the company is focused on building a strong dataset to support its selective mechanism of action and evaluate its potential clinical benefits in genetically defined cancer populations.
The completion of dose escalation in the Phase 1 study represents an important early milestone, and the upcoming expansion phases are expected to provide further insight into the therapy’s safety profile and anti-tumor activity.
With Fast Track Designation now in place, TER-2013 is positioned to benefit from closer regulatory engagement and potentially a more efficient development pathway as it progresses through clinical trials.
If successful, the program could represent a meaningful advancement in targeted cancer therapy by offering a more selective approach to inhibiting a critical oncogenic pathway while addressing the limitations of earlier generation AKT inhibitors.
About TER-2013
TER-2013 is an investigational, orally bioavailable small-molecule inhibitor designed to selectively target AKT1, maximizing target engagement within tumor cells. In preclinical studies, TER-2013 demonstrated potent and sustained inhibition of AKT1, while sparing AKT2, AKT3 and other off-target proteins at efficacious doses. This selectivity enables robust tumor response and durable anti-tumor activity across multiple xenograft models harboring PIK3CA, AKT1, or PTEN genetic alterations—without AKT2-dependent hyperglycemia, or other toxicities such as rash or diarrhea, observed with earlier pan-AKT inhibitors. TER-2013 is currently being evaluated in a Phase 1 clinical trial (NCT-07109726).
About Terremoto Biosciences
Terremoto Biosciences is a clinical-stage biotechnology company creating highly targeted, small molecule medicines with unmatched selectivity, potency and efficacy designed to deliver superior therapeutic benefit to patients. Terremoto is a private company supported by world-class investors and is based in South San Francisco and San Diego, California.
