A Long-Term Follow-Up Study of Participants Treated With A2 Biotherapeutics (A2 Bio) Gene Therapy (GT) Products

This is a long-term follow-up study designed to evaluate delayed safety events and long-term efficacy of A2 Bio GT products for participants who received any amount of A2 Bio GT products in a previous interventional study. No further interventional treatment is administered in this study.

Participants will enroll in this long-term follow-up study upon completion of 2 years of follow-up in the assigned interventional study in which they received treatment. Participants will be followed for up to 15 years after administration of A2 Bio GT product. This study will collect long-term safety and efficacy data as outlined by the FDA guidance for long-term follow-up for GT products.

• No additional intervention administered in this long term follow-up study (Other): Safety follow-up for A2 Bio GT products administered in a previous interventional study

Primary outcomes

• Long-term safety of previous A2 Bio GT treatment [15 years post treatment with A2 Bio GT product]: Long-term safety of previous A2 Bio GT treatment as determined by incidence of adverse events (AEs)

Secondary outcomes

• Overall survival [15 years post treatment with A2 Bio GT product]: The time from dosing of A2 Bio GT product to the date of death from any cause
• Long-term durability of clinical effect of previous A2 Bio GT treatment [15 years post treatment with A2 Bio GT product]: Long-term durability of clinical effect of previous A2 Bio GT treatment as measured by duration of response (DOR)
• Progression Free Survival (PFS) [15 years post treatment with A2 Bio GT product]: Time from dosing of A2 Bio GT products to the date of disease progression or death from any cause, whichever occurs earlier
• Incidence of RCL detected in blood [15 years post treatment with A2 Bio GT product]: RCL will be tested on blood by ddPCR as applicable based on FDA guidance

Other outcomes

• Progression Free Survival 2 (PFS2) [15 years post treatment with A2 Bio GT product]: Time from start of the next line of treatment after A2 Bio product to the date of disease progression or death from any cause, whichever occurs earlier
• Persistence of of A2 Bio GT [5 years post treatment with A2 Bio GT product]: Amount of A2 Bio GT present in patients treated with A2 Bio GT as assessed by Polymerase Chain Reaction (PCR) (or similar method) on participant blood samples

Sex: All, ages: 18 Years to any

Inclusion Criteria:

1. Received any amount of A2 Bio GT product on a previous A2 Bio interventional study
2. Able to provide written informed consent for this long-term follow-up study
3. Able to comply with study requirements

Exclusion Criteria:

1\. There are no specific exclusion criteria for this study

• Eric Ng, MD, Study director, A2 Biotherapeutics