Study of CM4620 to Reduce the Severity of Pancreatitis Due to Asparaginase

This is an open label safety and efficacy evaluation with comparison of toxicity to a historical control population (TOTXVI). There will be 3 cohorts of patients enrolled, and the dose for each cohort will be determined based on the toxicities experienced in the ongoing and prior cohorts. An initial 9 patients (cohort 1) will be enrolled and will receive dose level 1 and monitored for toxicity. If the therapy is well tolerated, 6 patients (cohort 2) will be treated at dose level 2. Subsequent enrollment of 9 patients (cohort 3) will be at either dose level 1 or 2 based on tolerability. The keyboard design will be used to determine the dosing for cohorts 2 and 3. Additional patients will be enrolled at the recommended phase II dose (RP2D) until a total of 24 patients have been treated at that dose, including any treated during the dose-finding phase. CM4620 will be given days 1-4 as an IV infusion beginning within 36 hours of the onset of acute pancreatitis associated abdominal pain and within 8 hours of enrollment. For patients with prior abdominal pain or in those unable to communicate the location/characteristic of their pain, a change in the characteristic of the pain or new enzyme elevation/imaging findings after previously normal studies will determine the timing of onset of pancreatitis. Patients will be followed for about 4 months after treatment.