Long-Term Follow-Up Study for Subjects Treated With P-BCMA-101

Per Health Authorities guidelines for gene therapy medicinal products that utilize
integrating vectors (FDA, 2006; Guidance for Industry, Gene Therapy Clinical Trials-Observing
Subjects for Delayed Adverse Events), long term safety and efficacy follow up of treated
subjects is required. Subjects are enrolled in this study following completion or early
discontinuation from a Poseida sponsored or supported study of P-BCMA-101 T cells and will be
followed for a total of 15 years post treatment from the last P-BCMA-101 treatment. Subjects
will be monitored for safety and efficacy to assess the risk of delayed adverse events (AEs)
and assess long-term efficacy, and PK and quantification of P-BCMA-101 T cells. Rimiducid may
be administered as indicated.

Study visits Subjects will only enter this protocol after completing or discontinuing from
their primary P-BCMA-101 protocol.

Once enrolled in this protocol a subject will return for regular follow-up depending on when
they last received P-BCMA-101 on their primary protocol:

- Every 3 months until the end of the first year after P-BCMA-101 treatment

- Every 6 months until the end of the third year after P-BCMA-101 treatment

- Then yearly until the end of the 15th year after P-BCMA-101 treatment (ie. if a patient
discontinues from their primary protocol 2 years after receiving P-BCMA-101, they will
be entering this study at the beginning of the 3rd year, and will remain on this study
for 13 years).

Subjects will undergo serial assessment of safety, chemistry, hematology, and disease
response as specified in the Schedule of Events. Subjects will further undergo a physical
exam and medical history, and concomitant medications, related AEs, new malignancies, new or
exacerbated clinically significant neurologic, hematologic, rheumatologic or other autoimmune
disorders will be recorded.

Inclusion Criteria:

- Subjects who have received P-BCMA-101 and completed or discontinued early from a
Poseida sponsored treatment protocol.

- Subject has provided informed consent.

Exclusion Criteria: