Subjects will be treated with HBM4003 in combination with Toripalimab for up to 2 years or until confirmed disease progression, unacceptable tolerability or treatment discontinuation through withdrawal of consent occurs, whichever happens first.~This trial consists of:~A screening period: 28 days~A treatment period: no longer than 2 years (Part 1 dose escalation study or Part 2 dose expansion)~A post-treatment follow-up period, including 28 days and 84 days after the last dose of study drug;~Survival follow-up.
To select RP2D/MTD of HBM4003 in combination with Toripalimab in dose confirmation part(Part 1) and use the RP2D in dose expansion part (Part 2) to evaluate the safety, tolerability, PK/PD and preliminary efficacy of in patients with advanced NEN and other solid tumors