Inclusion Criteria:

1a. Pathologically documented and definitively diagnosed non-resectable or metastatic
NSCLC with a RET fusion for patients who are either treatment naïve, or who have been
previously treated with systemic therapy. In the presence of a primary driver mutation,
such as EGFR, ALK, ROS1, NTRK, or BRAF, the patient must be treated with the appropriate
targeted therapy first. Patient is eligible if RET fusion is confirmed AND patient has
undergone initial therapy for his/her driver mutation, or

1b. Pathologically documented and definitively diagnosed RET mutation in advanced MTC
patients who are treatment naïve or who have been previously treated with MKI therapy, or

1c. Pathologically documented and definitively diagnosed advanced solid tumor with an
oncogenic RET fusion previously treated with standard of care appropriate for the tumor
type.

2. If previously treated with a selective RET inhibitor (e.g., RETEVMO), confirm
patient has not progressed but has discontinued due to adverse event(s).

3. Patient is not eligible for an ongoing study of pralsetinib or cannot access an
ongoing study of pralsetinib.

4. Patient is ≥ 12 years of age. 5. Patient has adequate vital organ function,
including heart, lungs, liver, kidneys, bone marrow and endocrine, and is expected
to tolerate therapy with a tyrosine kinase inhibitor.

6. No presence of clinically symptomatic interstitial lung disease or interstitial
pneumonitis, including radiation pneumonitis (i.e., affecting activities of daily
living or requiring therapeutic intervention).

7. Patient or patient's legal guardian, if permitted by local regulatory authorities,
intends to provide informed consent prior to the start of treatment with
pralsetinib.

8. Patient does not require therapy with a concomitant medication that is a strong
inhibitor or strong inducer of cytochrome P450 (CYP) 3A4.

9. Patient has not received treatment with any systemic anticancer therapy (except for
immunotherapy or other antibody therapies) and all forms of radiotherapy within 14
days or 5 half-lives prior to the first dose of pralsetinib. Pralsetinib may be
started within these washout periods if considered by the healthcare provider to be
safe and within the best interest of the patient, with prior Sponsor approval.

10. Patient has not received treatment with any immunotherapy or other antibody therapy
within 28 days prior to the first dose of pralsetinib (immune related toxicities
must have resolved to < Grade 2 prior to starting pralsetinib).

11. Patient has not had a major surgical procedure (minor surgical procedures such as
central venous catheter placement, tumor needle biopsy, and feeding tube placement
are not considered major surgical procedures) within 14 days prior to the first dose
of pralsetinib.

12. Women must be willing, if not postmenopausal or surgically sterile, to abstain from
sexual intercourse or employ highly effective contraception during pralsetinib
administration period and for at least 30 days after the last dose of pralsetinib.
Men, if not surgically sterile, must be willing to abstain from sexual intercourse
or employ highly effective contraception during pralsetinib administration period
and for at least 90 days after the last dose of pralsetinib.

13. Women must not be pregnant or breastfeeding.