Part 1 of this study will assess the safety and tolerability to establish the maximum tolerated dose (MTD) (or the maximum administered dose [MAD]) and/or the selected dose(s) of Sym024 in patients with solid tumor malignancies.~Part 2 of this study will assess the safety and tolerability to establish the MTD (or the MAD) and/or the selected dose(s) of Sym024 when administered in combination with Sym021 in patients with solid tumor malignancies.~Part 2a of this study will assess the safety and tolerability of Sym024 when first administered as a single agent during Cycle 1 (safety lead-in) followed by administration in combination with Sym021 during Cycle 2 and subsequent cycles.~Part 3 of this study will assess the safety of Sym024 when administered alone or in combination with Sym021 in expanded cohorts of patients with solid tumor malignancies.
The primary purpose of this study is to see if Sym024 is safe and tolerable as monotherapy and in combination with Sym021 in patients with solid tumor malignancies.