JL19001 Injection
DrugJL19001 Injection (100, 200, or 400 μg) will be administrated weekly for 6 consecutive weeks during induction treatment period, and then weekly for 3 consecutive weeks at month 3, 6, 9, 12, 18, 24, 30 and 36 during extension treatment period until disease progression, occurrence of unacceptable toxicity, withdrawal of informed consent, lost to follow-up, death, other reasons for withdrawal from treatment, or the end of treatment, whichever occurs earlier.