Wedoany.com Report-Dec.11, Roche announced on Wednesday that its investigational oral drug giredestrant reduced the risk of breast cancer recurrence by 30% compared with standard endocrine therapy in patients with early-stage ER-positive, HER2-negative disease. The company described the outcome as the most significant improvement in hormonal treatment for this condition in more than two decades.

Detailed findings from the phase III lidERA trial showed that, at three years, 92.4% of patients treated with giredestrant remained disease-free and alive, compared with 89.6% of those receiving standard endocrine therapy alone.

Roche had previously shared only topline results last month confirming that the study met its primary endpoint. Full data were presented on Wednesday at the San Antonio Breast Cancer Symposium.

"When you talk about a 30% increase in disease-free survival, you're basically saying 30% of these patients who in standard of care would still have gone on to recur - you're getting 30% fewer of those patients recurring," Levi Garraway, Roche's Chief Medical Officer, said in an interview.

ER-positive breast cancer represents approximately 70% of all diagnosed cases. Even with current standard treatments, up to one-third of patients with early-stage disease eventually experience recurrence, often years after initial therapy.

Giredestrant is an oral selective estrogen receptor degrader (SERD) designed to provide more complete estrogen receptor blockade than existing therapies. The safety profile appeared favorable, with fewer patients discontinuing treatment due to side effects compared with the control group, according to Garraway.

The results establish giredestrant as a potential new option for adjuvant endocrine therapy following surgery. Further analysis will determine which patients might still benefit from combination with CDK4/6 inhibitors, such as Novartis' Kisqali, in addition to giredestrant.

Analysts at JPMorgan have projected that, if approved for this indication, giredestrant could generate annual sales of approximately $5 billion at peak.

The lidERA trial enrolled patients with early-stage hormone receptor-positive breast cancer who had completed surgery and, where appropriate, chemotherapy. The study compared daily oral giredestrant against physician’s choice of standard endocrine therapy (tamoxifen or an aromatase inhibitor) over several years.

Roche plans to submit the data to health authorities worldwide for regulatory review. The treatment, if approved, would offer a convenient once-daily pill with improved efficacy over longstanding hormonal therapies while maintaining a manageable tolerability profile. The findings apply specifically to pharmaceutical development and clinical outcomes and do not involve product imports, exports, or consumption patterns.