This was a retrospective, longitudinal, observational study conducted using the Flatiron Health electronic health record (EHR)-derived database. BRAF+ advanced or metastatic (i.e., stage III or IV) melanoma patients treated at oncology practices across the US were identified for potential inclusion. All included patients were aged ≥18 years and required to have a diagnosis of melanoma (International Classification of Diseases (ICD)-9 172.x & ICD-10 C43 or D03x), a pathologic unresectable stage III or IV diagnosis, subsequent first-line (1L) treatment with either immunotherapy (IO) (nivolumab, pembrolizumab, ipilimumab + nivolumab) or targeted therapy (TT) dafratenib + trametinib (dab/tram) on or after 01 January 2014, and evidence of a BRAF-positive result at any point in time.

Inclusion criteria:

• Diagnosis of melanoma (ICD-9 172x & ICD-10 C43 or D03x)

• ≥2 documented clinical encounters on different days in the Flatiron network on or after 01 January 2011

• Pathologic unresectable stage III or IV at initial diagnosis after 01 January 2011, or earlier stage disease accompanied by development of a first locoregional recurrence after 01 January 2011

• Diagnosis of MM after 01 January 2011

• Evidence of a BRAF-positive result at any point in time

• Treatment with one of the following 1L therapies on or after 01 January 2014:

  • IO (nivolumab, pembrolizumab, or ipilimumab + nivolumab)
  • TT (dab/tram)

• At least 18 years of age at the time of initiation of 1L therapy

• At least 6-months of continuous follow-up from the time of initiation of 1L therapy

Exclusion Criteria:

• Lacking relevant unstructured documents (i.e., information such as free text from a physician note or pathology report that is captured systematically during the data abstraction process) in the Flatiron Health database
• Evidence of non-skin melanoma (ocular, subungual, mucosal, palmar, plantar)
• Documented receipt of a clinical study drug, defined as any uncancelled order, administration, or oral episode for a clinical study drug for cancer at any time prior to or during 1L treatment
• Presence of leptomeningeal disease (ICD-9 198.4 & ICD-10 C79.32 or C79.49)

This was a retrospective, noninterventional cohort study.