A phase I study of an agonist anti-CD27 human antibody (CDX-1127) in patients with advanced hematologic malignancies or solid tumors

Delivering co-stimulatory tumor necrosis factor receptor agonism for cancer immunotherapy: past, current and future perspectives

The tumor necrosis factor superfamily (TNFSF) and their receptors (TNFRSF) are important regulators of the immune system, mediating proliferation, survival, differentiation, and function of immune cells. As a result, their targeting for immunotherapy is attractive, although to date, under-exploited. In this review we discuss the importance of co-stimulatory members of the TNFRSF in optimal immune response generation, the rationale behind targeting these receptors for immunotherapy, the success of targeting them in pre-clinical studies and the challenges in translating this success into the clinic. The efficacy and limitations of the currently available agents are discussed alongside the development of next generation immunostimulatory agents designed to overcome current issues, and capitalize on this receptor class to deliver potent, durable and safe drugs for patients.

FcγRIIB as a key determinant of agonistic antibody efficacy

Fc gamma Receptor (FcγR) IIB (CD32B) is an immunoreceptor tyrosine inhibitory motif (ITIM)-bearing Fc receptor that is involved in abrogating the signalling and function delivered from other receptors; archetypally those arising from other, activatory, FcγR and from the B cell receptor (BCR) for antigen. In the context of immunotherapy, it has convincingly been shown to limit a variety of clinically important therapeutic monoclonal antibodies (mAb) such as rituximab and trastuzumab in preclinical models. However, recent exploration of so-called immunomodulatory mAb, for example agonist mAb directed against various members of the TNFR super-family, has cast new light on the ability of FcγRIIB to regulate immune responses and immunotherapy. These data, accumulated by several independent groups, have shown the seemingly paradoxical ability of FcγRIIB to augment or even be absolutely required for the activity of this class of mAb. In this review we highlight the key role of FcγRIIB in regulating agonistic mAb, detail the likely mechanism of action and propose new ways in which this information may be exploited therapeutically.