Nivolumab (OpdivoTM, BMS), a human IgG-4 mAb that blocks the Programmed cell death protein 1 (PD-1, CD279) has demonstrated anti-tumor activity in patients with various solid- and hematological neoplasms. Nivolumab has been registered by EMA and/or FDA for the treatment of patients with advanced melanoma, renal cell carcinoma (RCC), non-small cell lung cancer (NSCLC), and Hodgkin lymphoma. In a phase I dose escalation clinical trial, receptor blockade of PD-1 by nivolumab on circulating lymphocytes was maximal at a dose of 0,3 mg/kg. In patients with advanced melanoma nivolumab had a comparable tumor response rate at a dose range of 0.1 to 10 mg/kg q2wks. Nivolumab was further developed at a dose of 3 mg/kg q2wks and improved the overall survival of patients with advanced melanoma, NSCL, RCC and HNSCC.
Ipilimumab (YervoyTM, BMS), a human IgG-1 anti-CTLA-4 monoclonal antibody improves the overall survival of patients with advanced melanoma; and the relapse-free survival after complete resection of high-risk stage III melanoma. Animal models have established the safety and efficacy of intra-tumoral administration of ipilimumab. An intratumoral dose of CTLA-4 blocking mAb administered at a ratio of \[1:100\] compared to intravenous dosing was found to result in equivalent anti-tumor effect and was associated with less systemic toxicity.
Combined treatment with ipilimumab (3 mg/kg q3wks x4) plus nivolumab (1 mg/kg q3 wks x4 followed by 3 mg/kg q2 wks) further increases the tumor response rate and progression-free survival of patients with advanced melanoma and has been registered by EMA and FDA; this combination therapy is associated with a higher incidence of immune related adverse events. Nivolumab and ipilimumab have distinct immunological mechanisms that can be revealed by analyzing TCR usage in blood lymphocytes.
Preliminary safety and activity of nivolumab and its combination with ipilimumab in recurrent glioblastoma (CHECKMATE-143) were presented at the 2015 and 2016 ASCO Annual meetings (20 pts were treated, 10 in each arm). \[15\] All nivolumab related AEs were grade 1 or 2. Eight (80%) nivolumab plus ipilimumab treated patients experienced grade 3/4 AEs. Drug-related AEs leading to discontinuation occurred only in nivolumab plus ipilimumab patients (n = 5; 50%), including colitis, cholecystitis, diabetic ketoacidosis, confusion, and increased lipase. There were no drug-related deaths. Based on these experiences, the sponsor (BMS) decided to further investigate nivolumab as a mono-therapy in patients with recurrent- and newly diagnosed glioblastoma (CA209-143; CA209-498 and CA209-548). Antitumor activity of nivolumab has recently been established in children with recurrent glioblastoma that is characterized by biallelic mismatch repair deficiency.
Recent insight into the interplay of myeloid and lymphoid cells in the tumor microenvironment (TME) has indicated a pivotal role for myeloid dendritic cells (myDC) as key-mediators in mediating an adaptive anti-tumor immune response and also in "re-licensing" antitumoral CTL within the TME. Even when present in very low numbers, these cells play an essential role in "re-licensing" of antitumoral CTL within the TME. (Broz, Binnewies et al. 2014) CD1c (BDCA-1)+ myDC and CD141 (BDCA-3)+ myDC are able to capture tumor antigens in vivo. Through the cross presentation of tumor antigens CD1c (BDCA-1)+ myDC and CD141 (BDCA-3)+ myDC can coordinate an effective antitumoral T-cell response.