Under a Phase I dose escalation in prostate cancer, a 20% engraftment target was met or exceeded in three subjects with adequate safety, leading to study conclusion. Clinical responses were obtained but were suggested to be restrained by low plasma IL2 when depleted by high levels of engrafted activated T cells. This report presents a unique example of how the pharmaco-dynamics of "drug-drug" interactions may have a critical impact on the efficacy of their co-application. A new Pilot/Phase II trial is planned to test moderate dose IL2 (MDI) together with high dTc engraftments for anticipated improved therapeutic efficacy. Prostate 76:1257-1270, 2016. © 2016 Wiley Periodicals, Inc.

Purpose: This report describes the development and preclinical qualification tests of secondgeneration anti-carcinoembryonic (CEA) designerTcells for use in human trials. Experimental Design: The progenitor first-generation immunoglobulin-T-cell receptor (IgTCR) that transmits Signal 1-only effectively mediated chimeric immune receptor (CIR)^directed cytotoxicity, but expressor T cells succumbed to activation-induced cell death (AICD). The second-generation CIR (termed ''Tandem'' for two signals) was designed to transmit TCR Signal 1 and CD28 Signal 2 to render T cells resistant to AICD and provide prolonged antitumor effect in vivo. Results: A CIR was created that combines portions of CD28,TCR~, and a single chain antibody domain (sFv) specific for CEA into a single molecule (IgCD28TCR). As designed, the genemodified Tandem T cells exhibit the new property of being resistant to AICD, showing instead an accelerated proliferation on tumor contact. Tandem T cells are more potent than first generation in targeting and lysing CEA + tumor. Tandem T cells secrete high levels of interleukin-2 and IFNg on tumor contact that first-generationTcells lacked, but secretion was exhaustible, suggesting a need for interleukin-2 supplementation in therapy even for these second-generation agents. Finally, second-generationTcells were more effective in suppressing tumor in animal models. Conclusion: An advanced generation of anti-CEA designer T cells is described with features that promise a more potent and enduring antitumor immune response in vivo. These preclinical data qualify the human use of this agent that is currently undergoing trial in patients with CEA + cancers.

Purpose: CD40 ligand (CD40L, CD154) plays a central role in immunoregulation and also directly modulates epithelial cell growth and differentiation. We previously showed that the CD40 receptor is commonly expressed in primary breast cancer tissues. In this proof-of-principle study, we examined the breast cancer growth^regulatory activities of an oncolytic adenoviral construct carrying the CD40L transgene (AdEHCD40L). Experimental Design: In vitro and in vivo evaluations were carried out on AdEHCD40L to validate selective viral replication and CD40L transgene activity in hypoxia inducing factor-1a and estrogen receptor^expressing human breast cancer cells. Results: AdEHCD40L inhibited the in vitro growth of CD40 + human breast cancer lines (T-47D, MDA-MB-231, and BT-20) by up to 80% at a low multiplicity of infection of1. Incorporation of the CD40L transgene reduced the effective dose needed to achieve 50% growth inhibition (ED 50 ) by f10-fold. In contrast, viral and transgene expression of AdEHCD40L, as well its cytotoxicity, was markedly attenuated in nonmalignant cells. Intratumoral injections with AdEHCD40L reduced preexisting MDA-MB-231xenograft growth in severe combined immunodeficient mice by >99%and was significantly more effective (P < 0.003) than parental virus AdEH (69%) or the recombinant CD40L protein (49%).This enhanced antitumor activity correlated with cell cycle blockade and increased apoptosis in AdEHCD40L-infected tumor cells. Conclusions: These novel findings, together with the previously known immune-activating features of CD40L, support the potential applicability of AdEHCD40L for experimental treatment of human breast cancer.