• Priority Review recognizes the best-in-class potential of the inavolisib-based regimen for patients in urgent need of new treatment options 
• Additional analyses of INAVO120 will be presented in an oral abstract session at the 2024 American Society of Clinical Oncology Annual Meeting 
• The target action date for the FDA decision is November 27, 2024 

SOUTH SAN FRANCISCO, Calif. / May 29, 2024 / Business Wire / Genentech, a member of the Roche Group (SIX: RO, ROG; OTCQX: RHHBY), announced today that the U.S. Food and Drug Administration (FDA) has accepted the company’s New Drug Application and granted Priority Review to inavolisib, an investigational oral therapy, in combination with palbociclib (Ibrance®) and fulvestrant. The inavolisib-based regimen was evaluated in adult patients with PIK3CA-mutated, hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative, locally advanced or metastatic breast cancer, following recurrence on or within 12 months of completing adjuvant endocrine treatment.

The Priority Review is based on the positive Phase III INAVO120 results, which showed the inavolisib-based regimen more than doubled progression-free survival, reducing the risk of disease worsening or death by 57% compared to palbociclib and fulvestrant alone (15.0 months vs. 7.3 months; hazard ratio [HR]=0.43, 95% CI: 0.32-0.59, p<0.0001) in the first-line setting. Overall survival (OS) data were immature at the time of primary analysis, but a clear positive trend was observed (stratified HR=0.64, 95% CI: 0.43-0.97, p=0.0338 [boundary of 0.0098]). Follow-up for OS is continuing to the next analysis.

“The addition of inavolisib to standard of care treatment significantly delayed disease progression in the first-line setting and has the potential to extend survival for people with metastatic breast cancers that harbor PIK3CA mutations,” said Levi Garraway, M.D., Ph.D., Genentech’s chief medical officer and head of Global Product Development. “We welcome the FDA’s Priority Review designation for inavolisib, which underscores the urgency to bring this potential best-in-class treatment option to patients as quickly as possible.”

The PIK3CA mutation is found in approximately 40% of HR-positive metastatic breast cancers. Early testing for mutations like PIK3CA prior to initiating first-line treatment can help identify people who may benefit from targeted therapy.

Based on the Priority Review designation, the FDA has set a Prescription Drug User Fee Act date of November 27, 2024. Data from INAVO120 are also being used for filing submissions to other global health authorities, including the European Medicines Agency. Priority Review designation is granted to medicines that the FDA has determined to have the potential to provide significant improvements in the treatment, prevention or diagnosis of a disease.

Genentech recently announced the inavolisib-based regimen has been granted FDA Breakthrough Therapy Designation based on INAVO120, the 29th for Genentech’s oncology portfolio. Additional analyses of INAVO120 will be presented in an oral abstract session at the 2024 American Society of Clinical Oncology Annual Meeting, taking place May 31 - June 4.

Inavolisib is currently being investigated in three company-sponsored Phase III clinical studies (INAVO120, INAVO121, INAVO122) in PIK3CA-mutated locally advanced or metastatic breast cancer in various combinations. We continue to evaluate potential clinical development program expansion opportunities to address patient unmet needs in various tumor types across oncology.

About inavolisib

Inavolisib is an investigational, oral targeted treatment with best-in-class potential that could provide well-tolerated, durable disease control and potentially improved outcomes for people with PIK3CA-mutated, hormone receptor-positive, human epidermal growth factor receptor 2-negative, locally advanced or metastatic breast cancer, who often have a poor prognosis and are in urgent need of new treatment options. Inavolisib has been designed to help minimize the overall burden and toxicity of treatment and is differentiated from other PI3K inhibitors due to its high potency and specificity for the PI3K alpha isoform versus other isoforms, and unique mechanism of action that facilitates the degradation of mutated PI3K alpha.

About the INAVO120 study

The INAVO120 study [NCT04191499] is a Phase III, randomized, double-blind, placebo-controlled study evaluating the efficacy and safety of inavolisib in combination with palbociclib and fulvestrant versus placebo plus palbociclib and fulvestrant in people with PIK3CA-mutated, hormone receptor (HR)-positive, human epidermal growth factor receptor 2 (HER2)-negative, locally advanced or metastatic breast cancer whose disease progressed during treatment or within 12 months of completing adjuvant endocrine therapy and who have not received prior systemic therapy for metastatic disease.

The study included 325 patients, who were randomly assigned to either the investigational or control treatment arm. The primary endpoint is progression-free survival, as assessed by investigators, defined as the time from randomization in the clinical trial to the time when the disease progresses, or a patient dies from any cause. Secondary endpoints include overall survival, objective response rate, and clinical benefit rate.

Beyond INAVO120, inavolisib is currently being investigated in two additional company-sponsored Phase III clinical studies in PIK3CA-mutated locally advanced or metastatic breast cancer in various combinations:

• in combination with fulvestrant versus alpelisib plus fulvestrant in HR-positive/HER2-negative breast cancer post cyclin-dependent kinase 4/6 inhibitor and endocrine combination therapy (INAVO121; NCT05646862), and

• in combination with dual HER2 blockade versus dual HER2 blockade and optional physician's choice of endocrine therapy as a maintenance treatment in HER2-positive disease (INAVO122; NCT05894239).

About Hormone Receptor-Positive Breast Cancer

HR-positive breast cancer is the most prevalent type of all breast cancers, accounting for approximately 70% of cases. A defining feature of HR-positive breast cancer is that its tumor cells have receptors that attach to one or both hormones – estrogen or progesterone – which can contribute to tumor growth. People diagnosed with HR-positive metastatic breast cancer often face the risk of disease progression and treatment side effects, creating a need for additional treatment options. The PI3K signaling pathway is commonly dysregulated in HR-positive breast cancer, often due to activating PIK3CA mutations, which have been identified as a potential mechanism of intrinsic resistance to standard of care endocrine therapy in combination with cyclin-dependent kinase 4/6 inhibitors.

About Genentech in Breast Cancer

Genentech has been advancing breast cancer research for more than 30 years with the goal of helping as many people with the disease as possible. Our medicines, along with companion diagnostic tests, have contributed to bringing breakthrough outcomes in HER2-positive and triple-negative breast cancers. As our understanding of breast cancer biology rapidly improves, we are working to identify new biomarkers and approaches to treatment for other subtypes of the disease, including estrogen receptor-positive breast cancer, which is a form of hormone receptor-positive breast cancer, the most prevalent type of all breast cancers.

About Genentech

Founded more than 40 years ago, Genentech is a leading biotechnology company that discovers, develops, manufactures and commercializes medicines to treat patients with serious and life-threatening medical conditions. The company, a member of the Roche Group, has headquarters in South San Francisco, California. For additional information about the company, please visit http://www.gene.com.

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