Combination Therapy with Vincristine, Immunoglobulin and Glucocorticosteroid (VIG Regimen) is Very Effective for the Management of Grade 3/4 or Steroid-Refractory Immune-Related Adverse Events (irae) Secondary to PD-1 Blockade.

e14577 Background: The management of grade 3/4 or steroid-refractory immune related adverse events (irAE) is based on a paucity of retrospective data analysis. Our initial experience with the combination therapy with Vincristine (VCR), immunoglobulin (IVIG) and glucocorticosteroid (VIG regimen) showed clinical improvement in a wide variety of irAEs. As a result, we recommend the use of VIG regimen for the management of grade 3/4 or steroid-refractory irAEs. Methods: The character and clinical course of irAEs were abstracted from the medical record and analyzed. The components of VIG regimens are as follows: Methylprednisolone (MP) 2-10mg/kg for 3days, VCR 1.4mg/m2 (≤2mg) continuous infusion for 4-8 hours on day 3 once a week with Immunoglobulin (IVIG) 0.4g/kg for 3-5 days. The dose of MP and IVIG will be reduced quickly after irAE improves. VCR 1.4mg/m2 once a week will be used for 1 to 3 times according to the improvement. Clinical improvement was defined as either: documentation of resolution of symptoms and normalisation of biochemical tests or hospital discharge within 14 days. Results: A total of 25 patients had grade3/4 or steroid-refractory irAEs after receiving immune checkpoint inhibitors and then received VIG regimen. Among them, 22 patients have been significantly improved, with an improvement rate of 88%. Twenty-three patents were treated in the inpatient setting (92%). The index grade 3/4 irAE was pneumonitis in 28%, immune mediated hepatotoxicity(IMH) in 28%, rash/SJS/TEN in 24%, cerebritis in 8 % and one case each of ITP, Near blindness and severe oral mucositis. In 7 patients with severe IMH, the range of total bilirubin was 80-481umol/L and ALT 35-5000u/L. Six patients with IMH recover well but one patient did not recover to normal due to IMH complicated with pneumonitis and TEN . Clinical improvement was noted in 22/25 patients (88%), 11 patients (44%) required a single dose, while 12 patients (48%) required two doses, 2 patients(8%) required three doses of VCR 1.4mg/m2 continuous infusion for 4-8 hours. What is impressive is that the two patients with encephalitis were significantly relieved within 2 weeks after using the VIG regimen. One patient with TEN (SCORETEN 3)was significantly improved and discharged from our hospital 11 days after using the VIG regimen. A patient with near-blind eyesight recovered to normal 3 days after using the VIG regimen. Conclusions: VIG regimen may be an effective therapeutic option for the management of grade3/4 or steroid-refractory irAEs secondary to immune checkpoint blockade. However, randomized trials are needed to better elucidate the efficacy and safety of VIG regimen.