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Study VNC-236-101 is an open-label, multicenter, Phase 1, dose-escalation study with monotherapy VIP236 for the treatment of patients with metastatic tumors who have exhausted all standard therapy options. The study’s main objective is to determine a safe dose and schedule for VIP236 for further clinical development.

Fifteen patients have been dosed to date on the once every three weeks (Q3W) schedule. Sequential dose escalation cohorts with the Q3W schedule were 0.2 mg/kg (n=2), 0.4 mg/kg (n=5), 0.6 mg/kg (n=5), and 0.8 mg/kg (n=3). Results of the Q3W schedule (n=15) show:

The patient population is typical of a Phase 1 study with heavily pretreated patients and a wide range of tumor types.

The Q3W schedule is well tolerated with no dose-limiting toxicity (DLT) in any patients, and no patients have discontinued VIP236 due to an adverse event. Importantly, no severe or life-threatening diarrhea has been observed, validating the purposeful design of VIP236’s optimized camptothecin payload.

First efficacy assessment was at the end of cycle 2 (i.e., after only two doses on the Q3W schedule). Seven patients have achieved objective stable disease, including tumor reduction. Four patients remain on study with the longest treated patient on study for 168 days.

Dose escalation continues on the Q3W schedule.

Study VNC-943-101 is an open-label, multicenter, Phase 1 dose-escalation study with monotherapy VIP943 for the treatment of patients with CD123⁺ acute myeloid leukemia (AML), B-cell acute lymphocytic leukemia (B-ALL), or myelodysplastic syndromes (MDS) who have exhausted standard therapeutic options. The study’s main objective is to determine a safe dose and schedule for VIP943 for further clinical development.

VIP943 is administered once per week. Three patients were dosed in Cohort 1 (0.2 mg/kg) and four patients were dosed in Cohort 2 (0.4 mg/kg).

Despite the initial low doses in the study, all seven sequentially enrolled patients completed the 28-day DLT evaluation period. Five out of seven received a cycle 2 dose and two of these patients started cycle 3. One patient with MDS is still on study on cycle 3.

No DLTs occurred in Cohort 1 and 2. Four patients have been enrolled in Cohort 3 (0.7 mg/kg) and are undergoing DLT assessment.

VIP943 PK data shows very little free payload in circulation, consistent with the favorable safety profile observed preclinically and clinically.

On April 8, 2024, the Company reported preclinical experiments applying the next-generation effector chemistry of its VersAptx platform to the antibodies of approved ADCs, TRODELVY and ENHERTU, demonstrating the potential to improve tumor toxicity of ADCs by orders of magnitude.

In vitro tumor models, the Company’s sacituzumab-legumain-KSPi ADC had a 20-fold improvement in tumor toxicity compared with TRODELVY (sacituzumab-govitecan). The Company’s trastuzumab-legumain-KSPi ADC demonstrated an 8-fold increase in tumor toxicity compared with ENHERTU (fam-trastuzumab-deruxtecan).

These findings further support the versatility of VersAptx to address multiple cancer types, including solid tumors, and increase the efficacy and safety of ADCs. Further studies will be conducted in animal models.