Glofitamab in Relapsed/Refractory Mantle Cell Lymphoma: Results From a Phase I/II Study.

PURPOSE: Patients with relapsed/refractory (R/R) mantle cell lymphoma (MCL) have a poor prognosis. The phase I/II NP30179 study (ClinicalTrials.gov identifier: NCT03075696) evaluated glofitamab monotherapy in patients with R/R B-cell lymphomas, with obinutuzumab pretreatment (Gpt) to mitigate the risk of cytokine release syndrome (CRS) with glofitamab. We present data for patients with R/R MCL. METHODS: Eligible patients with R/R MCL (at least one previous therapy) received Gpt (1,000 or 2,000 mg) 7 days before the first glofitamab dose (single dose or split over 2 days if required). Glofitamab step-up dosing was administered once a day on days 8 (2.5 mg) and 15 (10 mg) of cycle 1, with a target dose of 16 or 30 mg once every 3 weeks from cycle 2 day 1 onward, for 12 cycles. Efficacy end points included investigator-assessed complete response (CR) rate, overall response rate (ORR), and duration of CR. RESULTS: Of 61 enrolled patients, 60 were evaluable for safety and efficacy. Patients had received a median of two previous therapies (range, 1-5). CR rate and ORR were 78.3% (95% CI, 65.8 to 87.9) and 85.0% (95% CI, 73.4 to 92.9), respectively. In patients who had received previous treatment with a Bruton tyrosine kinase inhibitor (n = 31), CR rate was 71.0% (95% CI, 52.0 to 85.8) and ORR was 74.2% (95% CI, 55.4 to 88.1). CRS after glofitamab administration occurred in 70.0% of patients, with a lower incidence in the 2,000 mg (63.6% [grade ≥2, 22.7%]) versus 1,000 mg (87.5%; grade ≥2, 62.5%) Gpt cohort. Four adverse events led to glofitamab withdrawal (all infections). CONCLUSION: Fixed-duration glofitamab induced high CR rates in heavily pretreated patients with R/R MCL; the safety profile was manageable with appropriate support.

Second-line rituximab-bendamustine versus rituximab-gemcitabine-oxaliplatin in diffuse large B-cell lymphoma in the real world.

Aim: Despite long-term responses to first-line immunochemotherapy, many patients with diffuse large B-cell lymphoma (DLBCL) have relapsed/refractory disease. Second-line treatment options are available. However, a large proportion of patients are ineligible for transplantation/intensive therapy. Patients & methods: This observational study of 702 patients in the USA, who used second-line therapies for relapsed/refractory DLBCL, evaluated treatment patterns and overall survival (OS). The study focused on the OS outcome of patients receiving second-line rituximab-bendamustine or rituximab-gemcitabine-oxaliplatin. Results & conclusion: Rituximab-bendamustine and rituximab-gemcitabine-oxaliplatin were received by 4.6 and 1.4% of patients, respectively (N = 42/702). Median and 1-year OS rates were similar between regimens. Many of the 200 different treatment regimens observed in second line were modified versions of National Comprehensive Cancer Network regimens.

Pattern of Onset and Risk Factors for Peripheral Oedema During Vildagliptin Use: Analysis from the Vildagliptin Prescription-Event Monitoring Study in England.

INTRODUCTION: Clinical trials have identified peripheral oedema (PO) as an adverse event of vildagliptin (an oral anti-diabetic drug [OAD]). A post-marketing study (PMS) was conducted to advance the understanding of vildagliptin use and particular safety concerns identified within the risk-management plan. PMS objectives included comparing the hazards between vildagliptin monotherapy and combination therapy for selected a priori identified risks, including PO. AIM: This study was a per-protocol supplementary analysis to investigate the pattern of onset and effect of vildagliptin combination therapy on PO risk. METHODS: The PMS used an observational cohort design. OAD exposure, selected risk factors and outcome data were collected from general practitioners in England regarding vildagliptin users for the 6-month period after starting treatment. Data analysis comprised univariate case/non-case analysis, time-to-onset analysis and Cox proportional hazard models to estimate hazard ratios (HR) of PO adjusting for selected patients' baseline characteristics. RESULTS: The study cohort included 4828 patients (median age 63 years; interquartile range [IQR] 54-71), 2692 of whom were male (55.8 %). The crude cumulative hazard of PO was 19.09 cases (95 % confidence interval [CI] 13.54-26.10) per 1000 person-years; 50 % of cases occurred during the first 34 days of treatment. A significantly faster time to PO onset was observed in patients prescribed concomitant sulfonylureas versus other treatment combinations (log rank test [LRT] p = 0.0365); in patients with a prior history of PO (LRT p < 0.001), arrhythmia (LRT p = 0.0003) or hypertension (LRT p = 0.0125); and in patients aged ≥60 years (LRT p = 0.0047). Similarly, the case/non-case univariate analysis indicated that patients with PO were older; had a higher prevalence of a history of either arrhythmia, hypertension or PO; and frequently used a sulfonylurea in combination. In the hazard function analysis, only sex and prior PO history had a profound effect on risk of PO after starting vildagliptin. Furthermore, effect modification was observed between sex and prior PO history; in male patients of average age (62 years), the HR was 12.84 (95 % CI 4.96-33.23); in females, it was 1.44 (95 % CI 0.32-6.40). CONCLUSIONS: In this planned supplementary analysis, the findings suggest that PO occurred most frequently within 1 month after starting treatment with vildagliptin, and previous PO history and male sex in elderly patients were important predictors of this risk. The observation that concomitant use of a sulfonylurea may also increase PO risk early after starting treatment should be taken into consideration if prescribing OADs in combination with vildagliptin.

Modulation of the tumor microvasculature by phosphoinositide-3 kinase inhibition increases doxorubicin delivery in vivo.

PURPOSE: Because effective drug delivery is often limited by inadequate vasculature within the tumor, the ability to modulate the tumor microenvironment is one strategy that may achieve better drug distribution. We have previously shown that treatment of mice bearing tumors with phosphoinositide-3 kinase (PI3K) inhibitors alters vascular structure in a manner analogous to vascular normalization and results in increased perfusion of the tumor. On the basis of that result, we asked whether inhibition of PI3K would improve chemotherapy delivery. EXPERIMENTAL DESIGN: Mice with xenografts using the cell line SQ20B bearing a hypoxia marker or MMTV-neu transgenic mice with spontaneous breast tumors were treated with the class I PI3K inhibitor GDC-0941. The tumor vasculature was evaluated by Doppler ultrasound, and histology. The delivery of doxorubicin was assessed using whole animal fluorescence, distribution on histologic sections, high-performance liquid chromatography on tumor lysates, and tumor growth delay. RESULTS: Treatment with GDC-0941 led to approximately three-fold increases in perfusion, substantially reduced hypoxia and vascular normalization by histology. Significantly increased amounts of doxorubicin were delivered to the tumors correlating with synergistic tumor growth delay. The GDC-0941 itself had no effect on tumor growth. CONCLUSION: Inhibition of PI3K led to vascular normalization and improved delivery of a chemotherapeutic agent. This study highlights the importance of the microvascular effects of some novel oncogenic signaling inhibitors and the need to take those changes into account in the design of clinical trials many of which use combinations of chemotherapeutic agents.

Quantitative analysis of tumor vascular structure after drug treatment.

This paper reports a method that aims to quantify the changes of tumour vascular structure as a result of drug treatment. The measures we have investigated to date include: vessel radii, inter-branch lengths, tortuosity and branch angles. We show that the distribution of vessel radii is better modelled as a gamma distribution as opposed to the log-normal distribution asserted by other researchers. We propose a new metric based on multiple linear regression to measure vascular tortuosity. We report statistical analyses which confirm that (as expected), at different significance levels, all the drugs we have tested (FTI, Iressa, Nelfinavir and PI-103) have positive effects in improving a tumour's vascular network. In each case, the changes are quantified.

Tumor vascular changes mediated by inhibition of oncogenic signaling.

Many inhibitors of the epidermal growth factor receptor (EGFR)-RAS-phosphatidylinositol 3-kinase (PI3K)-AKT signaling pathway are in clinical use or under development for cancer therapy. Here, we show that treatment of mice bearing human tumor xenografts with inhibitors that block EGFR, RAS, PI3K, or AKT resulted in prolonged and durable enhancement of tumor vascular flow, perfusion, and decreased tumor hypoxia. The vessels in the treated tumors had decreased tortuosity and increased internodal length accounting for the functional alterations. Inhibition of tumor growth cannot account for these results, as the drugs were given at doses that did not alter tumor growth. The tumor cell itself was an essential target, as HT1080 tumors that lack EGFR did not respond to an EGFR inhibitor but did respond with vascular alterations to RAS or PI3K inhibition. We extended these observations to spontaneously arising tumors in MMTV-neu mice. These tumors also responded to PI3K inhibition with decreased tumor hypoxia, increased vascular flow, and morphologic alterations of their vessels, including increased vascular maturity and acquisition of pericyte markers. These changes are similar to the vascular normalization that has been described after the antiangiogenic treatment of xenografts. One difficulty in the use of vascular normalization as a therapeutic strategy has been its limited duration. In contrast, blocking tumor cell RAS-PI3K-AKT signaling led to persistent vascular changes that might be incorporated into clinical strategies based on improvement of vascular flow or decreased hypoxia. These results indicate that vascular alterations must be considered as a consequence of signaling inhibition in cancer therapy.