Targeting HER2 with Trastuzumab Deruxtecan: A Dose-Expansion, Phase I Study in Multiple Advanced Solid Tumors.

HER2-targeted therapies are approved only for HER2-positive breast and gastric cancers. We assessed the safety/tolerability and activity of the novel HER2-targeted antibody-drug conjugate trastuzumab deruxtecan (T-DXd) in 60 patients with pretreated, HER2-expressing (IHC ≥ 1+), non-breast/non-gastric or HER2-mutant solid tumors from a phase I trial (NCT02564900). Most common (>50%) treatment-emergent adverse events (TEAE) were nausea, decreased appetite, and vomiting. Two drug-related TEAEs were associated with fatal outcomes. The confirmed objective response rate (ORR) was 28.3% (17/60). Median progression-free survival (PFS) was 7.2 [95% confidence interval (CI), 4.8-11.1] months. In HER2-mutant non-small cell lung cancer (NSCLC), ORR was 72.7% (8/11), and median PFS was 11.3 (95% CI, 8.1-14.3) months. Confirmed responses were observed in six tumor types, including HER2-expressing NSCLC, colorectal cancer, salivary gland cancer, biliary tract cancer, endometrial cancer, and HER2-mutant NSCLC and breast cancer. Results suggest T-DXd holds promise for HER2-expressing/mutant solid tumors. SIGNIFICANCE: T-DXd demonstrated promising activity in a heterogeneous patient population with heavily pretreated HER2-expressing or HER2-mutant solid tumors, especially HER2-mutant NSCLC. The safety profile was generally acceptable. Interstitial lung disease can be severe and requires prompt monitoring and intervention. Further research of T-DXd is warranted to address these unmet medical needs.See related commentary by Rolfo and Russo, p. 643.This article is highlighted in the In This Issue feature, p. 627.

Tumor Necrosis Factor-related apoptosis-inducing ligand (TRAIL) Receptor-1 and Receptor-2 agonists for cancer therapy.

IMPORTANCE OF THE FIELD: Agents that activate the TNF-related apoptosis-inducing ligand death receptors, TRAIL-R1 and TRAIL-R2, have attracted substantial attention and investment as potential anti-cancer therapies. Preclinical studies of TRAIL-R agonists indicate that they may be efficacious in a wide range of tumor types, especially when combined with chemotherapeutic agents. AREAS COVERED IN THIS REVIEW: The rationale for clinical development of TRAIL-R agonists is described, including the basis for combining these agents with other agents that modulate the 'checks and balances' of the apoptotic pathways. Accruing data that highlight differences between TRAIL-R1 and TRAIL-R2 that could affect the clinical significance of their specific agonists are described. The clinical experience to date with each of the agonists is summarized. WHAT THE READER WILL GAIN: The reader will gain an understanding of the rationale for the clinical development of TRAIL-R agonists, as well as the current status of clinical trials of these interesting new agents. TAKE HOME MESSAGE: Ongoing clinical trials will provide important information regarding the future development of TRAIL-R agonists.

Phase 2 study of mapatumumab, a fully human agonistic monoclonal antibody which targets and activates the TRAIL receptor-1, in patients with advanced non-small cell lung cancer.

BACKGROUND: Preclinical pharmacological properties of mapatumumab (agonistic human monoclonal antibody to TRAIL-R1) suggest that this antibody reduces cell viability, induces cell death in many types of cancer cell lines in vitro, inhibits or reduces tumor growth in xenograft models of solid tumors, and can induce significant tumor regression in some models. The receptor for mapatumumab, TRAIL-R1, is expressed on NSCLC cell lines. This pharmacologic profile suggests that mapatumumab may have therapeutic benefit in the treatment of NSCLC. METHODS: This Phase 2 multi-center study was designed to evaluate the efficacy, safety, and tolerability of mapatumumab in patients with advanced non-small cell lung cancer (NSCLC) previously treated with at least 1 platinum-based regimen. Each patient was to receive mapatumumab at a dose of 10mg/kg administered intravenously (IV) every 21 days in absence of disease progression. RESULTS: A total of 32 patients with relapsed or refractory Stage IIIB or IV or recurrent NSCLC were enrolled. Patients had received a median of 3 previous therapeutic regimens (range 1-7). Mapatumumab was well tolerated by the patients in this study with no discontinuations due to adverse events. The most common adverse events reported, regardless of relationship, were fatigue, cough, nausea, dyspnea, constipation, and vomiting. Laboratory analyses revealed no appreciable evidence of hepatic or renal toxicity among the study patients. No patients developed anti-mapatumumab antibodies. The plasma mapatumumab concentrations observed in this study were consistent with the predicted exposures, based on Phase 1 pharmacokinetic results. None of the 32 treated patients showed a response according to the RECIST criteria. Nine patients (29%) had stable disease (SD). CONCLUSION: In a group of heavily pretreated NSCLC patients, no objective single agent activity of mapatumumab was demonstrated, but the drug was safe and well tolerated. Based on this favorable safety profile, and preclinical evidence of potential synergy in combination with agents commonly used to treat NSCLC, future evaluation of mapatumumab in combination with chemotherapy is warranted.

Pharmacokinetics and in vitro and in vivo anti-tumor response of an interleukin-2-human serum albumin fusion protein in mice.

PURPOSE: Albuleukin fusion protein is a recombinant human interleukin-2 (rIL-2) genetically fused to recombinant human serum albumin (rHSA). The pharmacokinetics and pharmacologic activity of Albuleukin were examined in mice to determine whether the fusion protein had the immunomodulatory and anti-tumor properties of rIL-2 as well as a prolonged serum half-life due to the rHSA. METHODS: The effect of Albuleukin on lymphocyte proliferation, IL-2 receptor binding, and release of IFN-gamma from human NK cells were examined in vitro. For the pharmacokinetic analysis, Albuleukin and rIL-2 were administered intravenously (i.v.) and subcutaneously (s.c.) to BALB/c mice, both at a single dose of 500 microg/kg. The anti-tumor properties of Albuleukin were evaluated in a Renca tumor model in BALB/c mice and in a metastatic liver model of B16F10 melanoma in C57B1/6 mice. In the Renca tumor model, BALB/c mice were dosed intraperitoneally (i.p.) and s.c. with Albuleukin on days 12, 14, 16, 19, 21, and 23 and i.p. with rIL-2 daily for two periods of 5 days (days 10-14 and 17-21). In the B16 melanoma model, C57B1/6 mice were dosed s.c. with rIL-2 twice daily or Albuleukin every 48 h for 14 days. RESULTS: In vitro, Albuleukin induced the proliferation of primary human and mouse T cells and B cells and primary human NK cells, competed with rIL-2 for binding to the IL-2 receptors, and induced the production of IFN-gamma from primary human NK cells. The s.c. bioavailability of Albuleukin was about 45% relative to the i.v. dose. Plasma half-life was prolonged and ranged from 6 to 8 h with Albuleukin, compared to 19-57 min with rIL-2. Total clearance of Albuleukin was about 50-fold slower than that of rIL-2 after i.v. dosing. In vivo, Albuleukin suppressed the growth of Renca tumors and induced a dense infiltration of CD4+ and CD8+ T cells. Both Albuleukin and rIL-2 significantly reduced the tumor burden in mice with hepatic B16F10 metastases. Albuleukin significantly reduced the incidence of residual macroscopic hepatic tumors, resulting in improved survival relative to controls and rIL-2. CONCLUSION: Results from these studies suggest that the therapeutic efficacy of rIL-2 is improved in mice by prolonging its in vivo half-life through genetic fusion to albumin. Albuleukin, the fusion protein, had pronounced anti-tumor effects in Renca and hepatic melanoma tumor models without an increase in mortality. On the basis of its preclinical effects, Albuleukin was brought to the clinic to assess its therapeutic benefit in a variety of cancers.

Phase I and pharmacokinetic trial of the novel taxane BMS-184476 administered as a 1-hour intravenous infusion in combination with cisplatin every 21 days.

BMS-184476 is a 7-methylthiomethyl ether derivative of paclitaxel that displays potency superior to paclitaxel against tumor cells in culture and human tumor xenografts. It also inhibits the growth of paclitaxel-resistant human tumor cell lines with multidrug resistance mediated by either P-glycoprotein or mutated tubulin. Given the known synergy between taxanes and cisplatin in vitro and their clinical activity in combination, we performed a Phase I trial of BMS-184476 as a 1-h i.v. infusion followed by cisplatin every 21 days. Twenty-seven patients with a variety of solid tumors and good performance status received 116 cycles of therapy at BMS-184476 doses of 40-60 mg/m(2) together with cisplatin at 75 mg/m(2). The early observation of hypersensitivity reactions required prophylactic premedication in all patients. At the planned highest dose of BMS-184476 (60 mg/m(2)) and cisplatin (75 mg/m(2)), we observed dose-limiting toxicity in the form of neutropenia and diarrhea. Also at this level, five patients experienced grade 3 or worse nausea and vomiting. Aggressive prophylactic treatment eliminated the gastrointestinal toxicity. Mild to moderate peripheral neuropathy was infrequent, as was alopecia. Patient benefits included three partial responses in patients with mesothelioma, esophageal cancer, and head and neck cancer, and two additional minor responses. Plasma pharmacokinetic data are available for 23 patients treated at 40-60 mg/m(2). The mean maximum plasma concentrations and areas under the curves increased in a dose-related manner. The pharmacokinetics of BMS-184476 appeared independent of dose. The mean (+/- SE) values for clearance, volume of distribution at steady state, and the apparent terminal half-lives of the three dose groups during cycle 1 were 243 +/- 5 ml/min/m(2), 423 +/- 58 l/m(2), and 32.2 +/- 4.5 h, respectively. BMS-184476 60 at mg/m(2) with cisplatin at 75 mg/m(2) with appropriate supportive therapy is the dose recommended for further evaluation.

Phase I and pharmacokinetic study of the new taxane analog BMS-184476 given weekly in patients with advanced malignancies.

PURPOSE: The study was designed to establish the maximum administered dose and maximum tolerated dose (MTD) of BMS-184476, an analogue of paclitaxel, given weekly for 3 consecutive weeks every 28 days, later amended to a regimen of weekly administration for 2 consecutive weeks every 21 days. EXPERIMENTAL DESIGN: Adult patients with solid tumors received BMS-184476 i.v. on days 1, 8, and 15 without premedication. The trial followed a modified accelerated titration design. Doses of 7, 14, 28, 40, 50, and 60 mg/m(2)/wk were investigated. Pharmacokinetics of BMS-184476 in plasma and urine were investigated by high-performance liquid chromatography assay. RESULTS: Fifty-three patients were treated; the maximum administered dose was 60 mg/m(2)/wk, and the MTD was 50 mg/m(2)/wk. Dose-limiting neutropenia was the main toxicity. Neutropenia at the higher dose levels frequently prevented administration of the day 15 dose, and a modified schedule at MTD dosing on days 1 and 8 every 21 days was evaluated and found more feasible for Phase II studies. Diarrhea was the main nonhematological toxicity; other toxicities were vomiting, cumulative fatigue, and loss of appetite. Two patients died of neutropenia-related complications. Antitumor activity was observed in patients with breast and non-small cell lung cancer, with confirmed partial responses in 22% of patients. BMS-184476 was the main species found in the plasma with <5% present as paclitaxel or sulfoxide metabolites. The PKs of BMS-184476 appeared to be linear in the dose range of 7-60 mg/m(2). CONCLUSION: The recommended dose and schedule of weekly BMS-184476 is 50 mg/m(2) on days 1 and 8 every 21 days.