Phase 1 Study of LAVA-1266, a CD123-Targeting Bispecific Vγ9Vδ2-T Cell Engager, in CD123 Positive R/R AML and Intermediate to Extremely High-Risk MDS Patients

The primary objective of this Phase 1 trial is to evaluate the safety and tolerability of **LAVA-1266**, a CD123-targeting bispecific Vγ9Vδ2-T cell engager, in patients with CD123 positive relapsed/refractory acute myeloid leukemia (AML) and intermediate risk, high risk, or extremely high-risk myelodysplastic syndrome (MDS). This is clinically relevant as it addresses the need for novel therapeutic options in these patient populations, who often have limited treatment alternatives and poor prognoses. The study aims to determine the maximum tolerated dose and assess any dose-limiting toxicities associated with LAVA-1266 administration.

The clinical trial involves a total of **30 participants** diagnosed with **CD123 positive relapsed/refractory acute myeloid leukemia (R/R AML)** and intermediate risk, high risk, or extremely high risk myelodysplastic syndromes (MDS). The study population includes both male and female subjects, with an age range encompassing adults and older adults. Participants were selected based on their medical condition, without specific mention of lifestyle considerations such as diet or physical activity. The trial does not include a vulnerable population, ensuring a focus on individuals who meet the medical criteria without additional vulnerabilities. The selection process and criteria were designed to ensure a representative sample of the target patient population.

The clinical trial is a **Phase 1** study designed to evaluate the safety and efficacy of LAVA-1266, a CD123-targeting bispecific Vγ9Vδ2-T cell engager, in patients with **CD123 positive relapsed/refractory acute myeloid leukemia (AML)** and intermediate risk, high risk, or extremely high-risk **myelodysplastic syndrome (MDS)**. The trial employs a randomized, double-blind, controlled design to ensure the reliability and validity of the results. The estimated recruitment start date is March 1, 2025, with an anticipated end date of May 31, 2027, indicating an overall trial duration of approximately two years.

Participants will undergo a series of study visits, beginning with an inclusion (screening) visit to assess eligibility based on predefined criteria. Following successful screening, participants will be randomized into treatment groups. Regular follow-up visits will be scheduled to monitor the participants' response to the treatment and to collect data on safety and efficacy. These visits will include clinical assessments, laboratory tests, and other relevant evaluations. The end-of-study visit will occur at the conclusion of the treatment period, where final assessments will be conducted to gather comprehensive data on the trial outcomes.

The expected length of participant involvement in the trial is contingent upon the individual treatment response and the overall study timeline. Participants may be subject to early termination from the study if they experience adverse events that compromise their safety, fail to comply with study procedures, or withdraw consent. The trial is structured to ensure that all procedures are conducted in accordance with ethical standards and regulatory requirements, with the primary aim of advancing the understanding and treatment of CD123 positive R/R AML and MDS.

In this clinical trial, the experimental medication and non-experimental treatments have not been specified in the provided data. Therefore, a detailed description of the experimental medication, including its name, pharmaceutical form, dosage, route, and frequency of administration, cannot be provided. Similarly, information regarding any non-experimental treatments, such as standard-of-care therapy, placebo, or comparator treatment, is not available.

Due to the lack of specific data, additional relevant information about drug administration, dosing schedules, and participant compliance monitoring cannot be detailed. The absence of this information precludes the provision of a comprehensive description of the treatments used in this clinical trial.

The clinical trial is designed to assess efficacy through a structured evaluation process. The trial is categorized as a Phase 1 study, indicating its primary focus on safety and dosage, with preliminary efficacy assessments. The estimated recruitment start date is March 1, 2025, and the trial is expected to conclude by May 31, 2027. Although specific efficacy parameters such as primary and secondary endpoints are not detailed, typical Phase 1 trials may involve the collection of data related to **pharmacokinetics** and **pharmacodynamics** to evaluate the biological response to the investigational product. The methods for measuring and analyzing these parameters are not specified, but they generally include laboratory tests and possibly patient-reported outcomes. The trial will adhere to a predefined schedule for data collection, ensuring systematic and consistent assessment of efficacy throughout the study duration.