A phase I trial of LHC165 single agent and in combination with spartalizumab in patients with advanced solid malignancies.

BACKGROUND: LHC165 is a Toll-like receptor (TLR)-7 agonist that generates an effective tumor antigen-specific T-cell adaptive immune response as well as durable antitumor responses. We aimed to evaluate the safety, tolerability, efficacy, dose-limiting toxicities, and pharmacokinetics (PK) of LHC165 single agent (SA) ± spartalizumab [PDR001; anti-programmed cell death protein 1 (PD-1)] in adult patients with advanced solid tumors. MATERIALS AND METHODS: In this phase I/Ib, open-label, dose-escalation/expansion study, patients received LHC165 SA 100-600 µg biweekly through intratumoral (IT) injection and LHC165 600 µg biweekly + spartalizumab 400 mg Q4W through intravenous (IV) infusion. RESULTS: Forty-five patients were enrolled: 21 patients received LHC165 SA, and 24 patients received LHC165 + spartalizumab. The median duration of exposure was 8 weeks (range 2-129 weeks). No maximum tolerated dose was reached. Recommended dose expansion was established as LHC165 600 µg biweekly as SA and in combination with spartalizumab 400 mg Q4W. The most common drug-related adverse events (AEs) were pyrexia (22.2%), pruritus (13.3%), chills (11.1%), and asthenia (4.4%). The only serious AE (SAE) suspected to be related to the study drug was grade 3 pancreatitis (n = 1). Across all tumor types, overall response rate and disease control were 6.7% and 17.8%, respectively. Overall median progression-free survival (PFS) and immune-related PFS was 1.7 months. LHC165 serum PK demonstrated an initial rapid release followed by a slower release due to continued release of LHC165 from the injection site. CONCLUSIONS: LHC165 demonstrated acceptable safety and tolerability both as SA and in combination with spartalizumab, and evidence of limited antitumor activity was seen in adult patients with relapsed/refractory or metastatic solid tumors.

Effect of prematurely elevated late follicular progesterone on pregnancy outcomes following ovarian stimulation-intrauterine insemination for unexplained infertility: secondary analysis of the AMIGOS trial.

STUDY QUESTION: What is the relationship between late follicular phase progesterone levels and clinic pregnancy and live birth rates in couples with unexplained infertility undergoing ovarian stimulation with IUI (OS-IUI)? SUMMARY ANSWER: Late follicular progesterone levels between 1.0 and <1.5 ng/ml were associated with higher live birth and clinical pregnancy rates while the outcomes in groups with higher progesterone levels did not differ appreciably from the <1.0 ng/ml reference group. WHAT IS KNOWN ALREADY: Elevated late follicular progesterone levels have been associated with lower live birth rates after fresh embryo transfer following controlled ovarian stimulation and egg retrieval, but less is known about whether an association exists with outcomes in OS-IUI cycles. Existing studies are few and have been limited to ovarian stimulation with gonadotrophins, but the use of oral agents, such as clomiphene citrate and letrozole, is common with these treatments and has not been well studied. STUDY DESIGN, SIZE, DURATION: The study was a prospective cohort analysis of the Assessment of Multiple Intrauterine Gestations from Ovarian Stimulation (AMIGOS) randomized controlled trial. Frozen serum was available for evaluation from 2121 cycles in 828 AMIGOS participants. The primary pregnancy outcome was live birth per cycle, and the secondary pregnancy outcome was clinical pregnancy rate per cycle. PARTICIPANTS/MATERIALS, SETTING, METHODS: Couples with unexplained infertility in the AMIGOS trial, for whom female serum from day of trigger with hCG was available in at least one cycle of treatment, were included. Stored frozen serum samples from day of hCG trigger during treatment with OS-IUI were evaluated for serum progesterone level. Progesterone level <1.0 ng/ml was the reference group for comparison with progesterone categorized in increments of 0.5 ng/ml up to ≥3.0 ng/ml. Unadjusted and adjusted risk ratios (RR) and 95% CI were estimated using cluster-weighted generalized estimating equations to estimate modified Poisson regression models with robust standard errors. MAIN RESULTS AND THE ROLE OF CHANCE: Compared to the reference group with 110/1363 live births (8.07%), live birth rates were significantly increased in cycles with progesterone 1.0 to <1.5 ng/ml (49/401 live births, 12.22%) in both the unadjusted (RR 1.56, 95% CI 1.14, 2.13) and treatment-adjusted models (RR 1.51, 95% CI 1.10, 2.06). Clinical pregnancy rates were also higher in this group (55/401 clinical pregnancies, 13.72%) compared to reference group with 130/1363 (9.54%) (unadjusted RR 1.46, 95% CI 1.10, 1.94 and adjusted RR 1.42, 95% CI 1.07, 1.89). In cycles with progesterone 1.5 ng/ml and above, there was no evidence of a difference in clinical pregnancy or live birth rates relative to the reference group. This pattern remained when stratified by ovarian stimulation treatment group but was only statistically significant in letrozole cycles. LIMITATIONS, REASONS FOR CAUTION: The AMIGOS trial was not designed to answer this clinical question, and with small numbers in some progesterone categories our analyses were underpowered to detect differences between some groups. Inclusion of cycles with progesterone values above 3.0 ng/ml may have included those wherein ovulation had already occurred at the time the IUI was performed. These cycles would be expected to experience a lower success rate but pregnancy may have occurred with intercourse in the same cycle. WIDER IMPLICATIONS OF THE FINDINGS: Compared to previous literature focusing primarily on OS-IUI cycles using gonadotrophins, these data include patients using oral agents and therefore may be generalizable to the wider population of infertility patients undergoing IUI treatments. Because live births were significantly higher when progesterone ranged from 1.0 to <1.5 ng/ml, further study is needed to clarify whether this progesterone range may truly represent a prognostic indicator in OS-IUI cycles. STUDY FUNDING/COMPETING INTEREST(S): Oklahoma Shared Clinical and Translational Resources (U54GM104938) National Institute of General Medical Sciences (NIGMS). AMIGOS was funded by the Eunice Kennedy Shriver National Institute of Child Health and Human Development: U10 HD077680, U10 HD39005, U10 HD38992, U10 HD27049, U10 HD38998, U10 HD055942, HD055944, U10 HD055936, and U10HD055925. Research made possible by the funding by American Recovery and Reinvestment Act. Dr Burks has disclosed that she is a member of the Board of Directors of the Pacific Coast Reproductive Society. Dr Hansen has disclosed that he is the recipient of NIH grants unrelated to the present work, and contracts with Ferring International Pharmascience Center US and with May Health unrelated to the present work, as well as consulting fees with May Health also unrelated to the present work. Dr Diamond has disclosed that he is a stockholder and a member of the Board of Directors of Advanced Reproductive Care, Inc., and that he has a patent pending for the administration of progesterone to trigger ovulation. Dr Anderson, Dr Gavrizi, and Dr Peck do not have conflicts of interest to disclose. TRIAL REGISTRATION NUMBER: N/A.

A phase I trial of LXS196, a protein kinase C (PKC) inhibitor, for metastatic uveal melanoma.

BACKGROUND: Up to 50% of patients with uveal melanoma develop metastases (MUM) with a poor prognosis and median overall survival of approximately 1 year. METHODS: This phase I study evaluated the safety, tolerability, pharmacokinetics, pharmacodynamics and efficacy of the oral protein kinase C inhibitor LXS196 in 68 patients with MUM (NCT02601378). Patients received LXS196 doses ranging from 100-1000 mg once daily (QD; n = 38) and 200-400 mg twice daily (BID; n = 30). RESULTS: First cycle dose-limiting toxicities (DLTs) were observed in 7/38 (18.4%) QD and 2/17 (11.8%) BID patients. Hypotension was the most common DLT, occurring at doses ≥500 mg/day, and manageable with LXS196 interruption and dose reduction. Median duration of exposure to LXS196 was 3.71 months (range: 1.81-15.28) for QD and 4.6 months (range: 0.33-58.32) for BID dosing. Clinical activity was observed in 6/66 (9.1%) evaluable patients achieving response (CR/PR), with a median duration of response of 10.15 months (range: 2.99-41.95); 45/66 had stable disease (SD) per RECIST v1.1. At 300 mg BID, the recommended dose for expansion, 2/18 (11.1%) evaluable patients achieved PR and 12/18 (66.7%) had SD. CONCLUSION: These results suggest manageable toxicity and encouraging clinical activity of single-agent LXS196 in patients with MUM.

In-depth characterization of a new patient-derived xenograft model for metaplastic breast carcinoma to identify viable biologic targets and patterns of matrix evolution within rare tumor types

Metaplastic breast carcinoma (MBC) is a rare breast cancer subtype with rapid growth, high rates of metastasis, recurrence and drug resistance, and diverse molecular and histological heterogeneity. Patient-derived xenografts (PDXs) provide a translational tool and physiologically relevant system to evaluate tumor biology of rare subtypes. Here, we provide an in-depth comprehensive characterization of a new PDX model for MBC, TU-BcX-4IC. TU-BcX-4IC is a clinically aggressive tumor exhibiting rapid growth in vivo, spontaneous metastases, and elevated levels of cell-free DNA and circulating tumor cell DNA. Relative chemosensitivity of primary cells derived from TU-BcX-4IC was performed using the National Cancer Institute (NCI) oncology drug set, crystal violet staining, and cytotoxic live/dead immunofluorescence stains in adherent and organoid culture conditions. We employed novel spheroid/organoid incubation methods (Pu·MA system) to demonstrate that TU-BcX-4IC is resistant to paclitaxel. An innovative physiologically relevant system using human adipose tissue was used to evaluate presence of cancer stem cell-like populations ex vivo. Tissue decellularization, cryogenic-scanning electron microscopy imaging and rheometry revealed consistent matrix architecture and stiffness were consistent despite serial transplantation. Matrix-associated gene pathways were essentially unchanged with serial passages, as determined by qPCR and RNA sequencing, suggesting utility of decellularized PDXs for in vitro screens. We determined type V collagen to be present throughout all serial passage of TU-BcX-4IC tumor, suggesting it is required for tumor maintenance and is a potential viable target for MBC. In this study we introduce an innovative and translational model system to study cell–matrix interactions in rare cancer types using higher passage PDX tissue.

In-depth characterization of a new patient-derived xenograft model for metaplastic breast carcinoma to identify viable biologic targets and patterns of matrix evolution within rare tumor types.

Metaplastic breast carcinoma (MBC) is a rare breast cancer subtype with rapid growth, high rates of metastasis, recurrence and drug resistance, and diverse molecular and histological heterogeneity. Patient-derived xenografts (PDXs) provide a translational tool and physiologically relevant system to evaluate tumor biology of rare subtypes. Here, we provide an in-depth comprehensive characterization of a new PDX model for MBC, TU-BcX-4IC. TU-BcX-4IC is a clinically aggressive tumor exhibiting rapid growth in vivo, spontaneous metastases, and elevated levels of cell-free DNA and circulating tumor cell DNA. Relative chemosensitivity of primary cells derived from TU-BcX-4IC was performed using the National Cancer Institute (NCI) oncology drug set, crystal violet staining, and cytotoxic live/dead immunofluorescence stains in adherent and organoid culture conditions. We employed novel spheroid/organoid incubation methods (Pu·MA system) to demonstrate that TU-BcX-4IC is resistant to paclitaxel. An innovative physiologically relevant system using human adipose tissue was used to evaluate presence of cancer stem cell-like populations ex vivo. Tissue decellularization, cryogenic-scanning electron microscopy imaging and rheometry revealed consistent matrix architecture and stiffness were consistent despite serial transplantation. Matrix-associated gene pathways were essentially unchanged with serial passages, as determined by qPCR and RNA sequencing, suggesting utility of decellularized PDXs for in vitro screens. We determined type V collagen to be present throughout all serial passage of TU-BcX-4IC tumor, suggesting it is required for tumor maintenance and is a potential viable target for MBC. In this study we introduce an innovative and translational model system to study cell-matrix interactions in rare cancer types using higher passage PDX tissue.

Regulation of triple-negative breast cancer cell metastasis by the tumor-suppressor liver kinase B1.

Liver kinase B1 (LKB1), also known as serine/threonine kinase 11 (STK11), has been identified as a tumor suppressor in many cancers including breast. Low LKB1 expression has been associated with poor prognosis of breast cancer patients, and we report here a significant association between loss of LKB1 expression and reduced patient survival specifically in the basal subtype of breast cancer. Owing to the aggressive nature of the basal subtype as evidenced by high incidences of metastasis, the purpose of this study was to determine if LKB1 expression could regulate the invasive and metastatic properties of this specific breast cancer subtype. Induction of LKB1 expression in basal-like breast cancer (BLBC)/triple-negative breast cancer cell lines, MDA-MB-231 and BT-549, inhibited invasiveness in vitro and lung metastatic burden in an orthotopic xenograft model. Further analysis of BLBC cells overexpressing LKB1 by unbiased whole transcriptomics (RNA-sequencing) revealed striking regulation of metastasis-associated pathways, including cell adhesion, extracellular matrix remodeling, and epithelial-to-mesenchymal transition (EMT). In addition, LKB1 overexpression inhibited EMT-associated genes (CDH2, Vimentin, Twist) and induced the epithelial cell marker CDH1, indicating reversal of the EMT phenotype in the MDA-MB-231 cells. We further demonstrated marked inhibition of matrix metalloproteinase 1 expression and activity via regulation of c-Jun through inhibition of p38 signaling in LKB1-expressing cells. Taken together, these data support future development of LKB1 inducing therapeutics for the suppression of invasion and metastasis of BLBC.