Silverback Therapeutics Inc. (NASDAQ: SBTX) Reports Phase 1/1b SBT6050 Study Data In Combination With Pembrolizumab

Silverback Therapeutics Inc. (NASDAQ: SBTX) has presented interim results from its Phase1/1b SBT6050 clinical study as a monotherapy and combined with pembrolizumab in metastatic or metastatic or advanced HER2-expressing  patients at the 2021 European Society for Medical Oncology Congress. 

Silverback reports data on SBT6050’s pharmacological activity. 

CEO Laura Shawver said, “Over this past year, we have gathered compelling data with clear signals of SBT6050’s pharmacological activity, marked by the activation of both the innate and adaptive immune response in patients. We look forward to moving into expansion cohorts and to expanding our clinical development plan to include combination with standard-of-care trastuzumab-containing regimens.”

The SBT6050-101 trial included 40 patients with advanced or metastatic HER2-expressing or amplified solid tumors as of August 1, 2021. In the monotherapy dose-escalation arm, SBT6050 dose levels ranged from 0.3 to 1.2 mg/kg, while in the pembrolizumab combination arm, dose levels ranged from 0.15 to 0.3 mg/kg. In addition, SBT6050 was given to patients in doses ranging from 1-17. Notably, the company reported a good tolerability profile for SBT6050 both as a monotherapy and a combination with pembrolizumab.

Massachusetts General Hospital Medical Oncologist Samuel Klempner said, “The adverse event profile thus far has been very manageable and importantly, suggests the potential to combine with other standard of care agents The signals of anti-tumor activity are encouraging and its complementary mechanism of action with standard-of-care agents makes SBT6050 attractive for combination regimens.”

Anti-tumor activity reported on the subject population

There were early anti-tumor activity signals witnessed in heavily pre-treated heterogeneous patients. Out of the 18 evaluable subjects for tumor types of concern, one subject with HER2 IHC2+ NSCLC confirmed a partial response at 36 weeks after enrolment and eight weeks post-treatment.

SBT6050 targets HER2’s pertuzumab binding domain and is intended to be used in conjunction with standard-of-care medicines, such as trastuzumab-based regimens. Silverback will provide the specifics of its enhanced clinical development strategy in an investor webcast.