Tianfeng Securities Co.,Ltd. issued a research report stating that the NMPA recently approved the additional 100mg specification for SKB BIO-B's (06990) SKB264, which will further optimize clinical dosing regimens, enhance treatment convenience and compliance, and provide more accessible and economical treatment options for patients with advanced breast cancer and non-small cell lung cancer (NSCLC). Considering the smooth commercialization progress of the company's core products, the firm projects the company's operating revenue for 2025-2027 to be 2.084 billion yuan, 2.876 billion yuan, and 4.663 billion yuan respectively, upgrading the rating to "Buy."

Tianfeng Securities Co.,Ltd.'s main viewpoints are as follows:

Recent developments show that two key clinical studies of the company's core product Sacituzumab Govitecan (SKB264) - the OptiTROP-Lung04 study and OptiTROP-Breast02 study - have both been selected for Late-Breaking Abstracts (LBA) at the 2025 ESMO conference. Notably, OptiTROP-Lung04 has been selected for oral presentation at the Presidential Symposium. Only nine clinical studies worldwide were selected for the Presidential Symposium this year, with OptiTROP-Lung04 securing one spot, further demonstrating international academic recognition of SKB264's treatment potential in EGFR-mutated NSCLC.

**SKB264 Multi-dimensional Layout in NSCLC Field, Leading New Breakthroughs in Various Subtypes**

SKB264 has best-in-class potential in the lung cancer field. SKB264 was approved in March 2025 in mainland China for third-line treatment of EGFR-mutated non-squamous NSCLC. Beyond later-line treatment, Sacituzumab Govitecan has also made significant progress in exploring earlier-line treatments. The NDA for second-line NSCLC treatment following EGFR TKI failure in EGFR-mutated patients was accepted by CDE in October 2024 and included in priority review.

The NDA submission for 2L NSCLC indication is based on the OptiTROP-Lung04 trial, which was selected for oral presentation at the 2025 ESMO Presidential Symposium. OptiTROP-Lung04 is a Phase III clinical trial comparing SKB264 monotherapy versus pemetrexed plus platinum in EGFR-mutated NSCLC patients who failed EGFR-TKI treatment. Pre-specified interim analysis showed that SKB264 demonstrated statistically significant and clinically meaningful improvement in PFS, achieving the primary endpoint of BIRC-assessed PFS. Currently, both Gilead's and AstraZeneca/Daiichi Sankyo's TROP2 ADCs have failed to meet the primary OS endpoint in 2L NSCLC treatment.

Beyond breakthroughs in classic mutation TKI resistance, SKB264 effectively covers various rare mutations. The SKB264-II-08 study (Cohorts 5a and 5b) is a Phase II clinical trial of SKB264 monotherapy in previously treated rare EGFR-mutated NSCLC. Results showed that among patients with rare EGFR mutations including G719X, S768I, L861Q, and Exon 20 insertions, SKB264 achieved an ORR of 35.7%, DCR of 85.7%, and mPFS of 9.5 months. These rare mutations are all within the approved indication scope, providing new effective treatment options for rare EGFR-mutated patients who have long lacked standard therapies.

Additionally, for wild-type NSCLC first-line treatment, SKB264 is conducting a Phase III clinical trial in mainland China for PD-L1 TPS <1% patients and a global multicenter Phase III clinical trial for the PD-L1 TPS ≥50% subgroup. Phase II clinical studies have demonstrated superior efficacy compared to similar investigational drugs and existing therapies (non-head-to-head comparison).

**SKB264's Promising Future in BC Field, HR+/HER2- BC 2L+ Phase III Clinical Trial Meets Primary Endpoint**

In the breast cancer field, SKB264 shows broad application prospects. SKB264 was approved in November 2024 for second-line treatment of TNBC. Its NDA for second-line treatment of HR+/HER2- breast cancer was also accepted by CDE in May 2025 and included in priority review, potentially providing new treatment options for previously treated HR+/HER2- breast cancer patients.

This NDA is based on the OptiTROP-Breast02 study, which was selected for LBA at the 2025 ESMO conference. As a registrational Phase III clinical trial targeting HR+/HER2- breast cancer patients who previously received endocrine therapy and other systemic treatments in the advanced stage, OptiTROP-Breast02 has achieved its pre-specified primary endpoint. Interim analysis results showed that SKB264 monotherapy achieved statistically significant and clinically meaningful improvement in BIRC-assessed PFS, while also showing a benefit trend in OS.