Leveraging TROP2 Antibody-Drug Conjugates in Solid Tumors.

Antibody-drug conjugates (ADCs) have become the cornerstone of effective therapeutics in solid and hematological malignancies by harnessing potent cytotoxic payloads with targeted tumoricidal delivery. Since the monumental shift occurred with HER2-targeted ADCs, the discovery of the TROP2 antigen has revolutionized the landscape of ADC development. Moving beyond the traditional ADC design, multiple novel ADCs have successfully shaped and improved survival outcomes in patients with various tumor histologies. Here we review and contrast the clinical impact of the well-known TROP2 ADCs currently in clinical use. We also shed light on upcoming investigational TROP2 ADCs showing promise with novel ADC platforms.

RAF inhibitor re-challenge therapy in BRAF-aberrant pan-cancers: the RE-RAFFLE study.

Previous studies have shown the clinical benefit of rechallenging the RAF pathway in melanoma patients previously treated with BRAF inhibitors. 44 patients with multiple tumors harboring RAF alterations were rechallenged with a second RAF inhibitor, either as monotherapy or in combination with other therapies, after prior therapy with a first RAF inhibitor. This retrospective observational study results showed that rechallenging with RAFi(s) led to an overall response rate of 18.1% [PR in thyroid (1 anaplastic; 3 papillary), 1 ovarian, 2 melanoma, 1 cholangiocarcinoma, and 1 anaplastic astrocytoma]. The clinical benefit rate was 54.5%; more than 30% of patients had durable responses with PR and SD lasting > 6 months. The median progression-free survival on therapy with second RAF inhibitor in the rechallenge setting either as monotherapy or combination was shorter at 2.7 months (0.9-30.1 m) compared to 8.6 months (6.5-11.5 m) with RAF-1i. However, the median PFS with RAF-2i responders (PFS-2) improved at 12.8 months compared to 11.4 months with RAF-1i responders. The median OS from retreatment with RAF-2i was 15.5 months (11.1-30.8 m). Further prospective studies are needed to validate these results and expand targeted therapy options for RAF-aberrant cancers.

Phase 1b study of combined selinexor and eribulin for the treatment of advanced solid tumors and triple-negative breast cancer.

BACKGROUND: Selinexor (KPT-330) is a potent inhibitor of exportin 1 (XPO1), in turn inhibiting tumor growth. Selinexor enhances the antitumor efficacy of eribulin in triple-negative breast cancer (TNBC) in vitro and in vivo. Given the unmet medical need in TNBC and sarcoma, the authors explored the safety and efficacy of this combination. METHODS: The authors conducted a phase 1b trial of combined selinexor and eribulin using a 3 + 3 dose-escalation design in patients who had advanced solid tumors and in those who had TNBC in a dose-expansion cohort. RESULTS: Patients with TNBC (N = 19), sarcoma (N = 9), and other cancers (N = 3) were enrolled in the dose-escalation cohort (N = 10) and in the dose-expansion cohort (N = 21). The median number lines of prior therapy received was four (range, from one to seven prior lines). The most common treatment-related adverse events for selinexor were nausea (77%), leukopenia (77%), anemia (68%), neutropenia (68%), and fatigue (48%). One dose-limiting toxicity occurred at the first dose level with prolonged grade 3 neutropenia. The recommended phase 2 dose was 80 mg of selinexor orally once per week and 1 mg/m2 eribulin on days 1 and 8 intravenously every 3 weeks. The objective response rate (ORR) was 10% in three patients. In the dose-escalation cohort, the ORR was 10%, whereas six patients with had stable disease. In the TNBC dose-expansion cohort (n = 18), ORR was 11%, and there were two confirmed partial responses with durations of 10.8 and 19.1 months (ongoing). CONCLUSIONS: Selinexor and eribulin had an acceptable toxicity profile and modest overall efficacy with durable responses in select patients. PLAIN LANGUAGE SUMMARY: Effective therapies for advanced, triple-negative breast cancer and sarcoma represent an unmet need. Exportin 1 is associated with the transport of cancer-related proteins. Preclinical studies have demonstrated tumor growth inhibition and enhanced tumor sensitivity in patients who receive selinexor combined with eribulin. In this phase 1b study, the authors evaluated the safety profile and clinical activity of the combination of selinexor, a potent oral inhibitor of exportin 1, and eribulin in patients with advanced cancers enriched for triple-negative breast cancer or sarcoma. The combination was well tolerated; most adverse events were mild or moderate, reversible, and managed with dose modifications or growth factor support. The combination of selinexor and eribulin produced an antitumor response, particularly in some patients with triple-negative breast cancer. This work lays the foundation for prospective investigations of the role of selinexor and eribulin in the treatment of triple-negative breast cancer.

A Phase I Trial of Bevacizumab and Temsirolimus in Combination With Valproic Acid in Advanced Solid Tumors.

BACKGROUND: Preclinical models suggest synergy between anti-angiogenesis therapy, mammalian target of rapamycin (mTOR), and histone deacetylase inhibitors to promote anticancer activity. METHODS: This phase I study enrolled 47 patients between April 2012 and 2018 and determined safety, maximum tolerated dose (MTD), and dose-limiting toxicities (DLTs) when combining bevacizumab, temsirolimus, and valproic acid in patients with advanced cancer. RESULTS: Median age of enrolled patients was 56 years. Patients were heavily pretreated with a median of 4 lines of prior therapy. Forty-five patients (95.7%) experienced one or more treatment-related adverse events (TRAEs). Grade 3 TRAEs were lymphopenia (14.9%), thrombocytopenia (8.5%), and mucositis (6.4%). Grade 4 TRAEs included lymphopenia (2.1%) and CNS cerebrovascular ischemia (2.1%). Six patients developed DLTs across 10 dose levels with grade 3 infection, rash, mucositis, bowel perforation, elevated lipase, and grade 4 cerebrovascular ischemia. The MTD was dose level 9 (bevacizumab 5 mg/kg days 1 and 15 intravenously (IV) plus temsirolimus 25 mg days 1, 8, 15, and 22 IV and valproic acid 5 mg/kg on days 1-7 and 15-21 per orally (PO)). Objective response rate (ORR) was 7.9% with confirmed partial response (PRs) in 3 patients (one each in parotid gland, ovarian, and vaginal cancers). Stable disease (SD) ≥+6 months was seen in 5 patients (13.1%). Clinical benefit state (CBR: PR + SD ≥+6 months) was 21%. CONCLUSION: Combination therapy with bevacizumab, temsirolimus, and valproic acid was feasible, but there were numerous toxicities, which will require careful management for future clinical development (ClinicalTrials.gov Identifier: NCT01552434).

Safety and Efficacy of Immune Checkpoint Inhibitors in Patients with Cancer and Viral Hepatitis: The MD Anderson Cancer Center Experience.

BACKGROUND: Despite the clinical benefit of immune checkpoint inhibitors (ICIs), patients with a viral hepatitis have been excluded from clinical trials because of safety concerns. The purpose of this study was to determine the incidence rate of adverse events (AEs) in patients with viral hepatitis who received ICIs for cancer treatment. MATERIALS AND METHODS: We conducted a retrospective study in patients with cancer and concurrent hepatitis B or C, who had undergone treatment with ICI at MD Anderson Cancer Center from January 1, 2010 to December 31, 2019. RESULTS: Of the 1076 patients screened, we identified 33 with concurrent hepatitis. All 10 patients with HBV underwent concomitant antiviral therapy during ICI treatment. Sixteen of the 23 patients with HCV received it before the initiation of ICI. The median follow-up time was 33 months (95% CI, 23-45) and the median duration of ICI therapy was 3 months (IQR, 1.9-6.6). Of the 33 patients, 12 (39%) experienced irAEs (immune-related adverse events) of any grade, with 2 (6%) having grade 3 or higher. None of the patients developed hepatitis toxicities. CONCLUSION: ICIs may be a therapeutic option with an acceptable safety profile in patients with cancer and advanced liver disease.

On target methods to induce abscopal phenomenon for Off-Target effects: From happenstance to happenings.

Although the "abscopal phenomenon" has been described several decades ago, this phenomenon lately has been obtaining momentous traction with the dawn of immune-based therapies. There has been increased cross talk among radiation oncologists, oncologists and immunologists and consequently a surge in the number of prospective clinical trials. This must be coupled with translation work from these clinical trials to aid in eventual identification of patients who may benefit. Abscopal effects may be induced by local and systemic methods, conventional radiotherapy, particle radiation, radionucleotide methods, cryoablation and brachytherapy. These approaches have all been reported to be stimulate abscopal effect. Immune induction by immune checkpoint therapy, immune adjuvants, cellular therapy including CAR and NK cell therapies may generate systemic abscopal response. With increasing recognition of this effect, there remains a lot of work to explore the modalities of inducing abscopal responses and ultimate prediction or prognostication on stratifying who may benefit. Ultimately, there is an urgent need for prospective studies and data to tease apart which one of these modalities can be applied to the appropriate candidate, to the appropriate cancer at the appropriate setting. This review seeks to elucidate readers on the different modalities of radiation, systemic therapies and other techniques rarely explored to potentiate the abscopal effect from a mere coincidence to a finite occurrence.

Predicting the Abscopal Effect: Associated Tumor Histologic Subtypes and Biomarkers.

Radiotherapy is a pillar of cancer treatment, which has historically been used primarily to treat localized disease with curative intent. With the increasing role of radiotherapy for metastatic disease and rapid integration of immunotherapy into the standard of care for various cancers, it has been observed that local radiation to one malignant site can lead to shrinkage of tumors at other sites, a phenomenon termed the "abscopal effect." Historically, there was little mechanistic elucidation as to how this phenomenon occurs. However, multiple groups have recently identified associated immuno-prognostic factors, such as high post-radiotherapy absolute lymphocyte count, neoantigens, myeloid-derived suppressor cells, and NK cells. The concomitant use of immunotherapy with radiotherapy has been documented to induce the abscopal effect. As immunotherapies continue to be incorporated into most cancer treatment approaches, understanding which patients are more likely to benefit from an abscopal effect may allow for optimization of both systemic and radiotherapeutic strategies. This review highlights the tumor histologic subtypes and biomarkers of the greatest utility for the recognition and identification of patients likely to benefit from the abscopal effect.

The abscopal effect in patients with cancer receiving immunotherapy.

Interest in the abscopal effect has been rekindled over the past decade with the advent of immunotherapy. Although purportedly elusive, this phenomenon is being increasingly reported. Venturing further using a multimodality approach with an array of systemic agents and unconventional modalities is direly needed. In this perspective, we describe the fundamentals of abscopal responses (ARs), explore combinations with systemic therapies that hold promise in eliciting ARs, and reconnoiter unconventional modalities that may induce ARs. Finally, we scrutinize prospective agents and modalities that exhibit preclinical ability to elicit ARs and discuss prognostic biomarkers, their limitations, and pathways of abscopal resistance for reproducibility.

Histological transformation to gliosarcoma with combined BRAF/MEK inhibition in BRAF V600E mutated glioblastoma.

The identification of BRAF V600 mutation in multiple cancers beyond melanoma and the development of combined BRAF and MEK targeting agents have altered the landscape of tissue-agnostic precision oncology therapies with an impact on survival outcomes. Despite initial efficacy, resistance emerges, and it is pertinent to identify putative resistance mechanisms. We report a case of recurrent glioblastoma (GBM) harboring BRAF V600E alteration who initially responded to combined BRAF + MEK inhibition and subsequently developed treatment resistance by histological transformation to gliosarcoma and acquisition of oncogenic KRAS G12D and an NF1 L1083R mutation. This documented case represents an initial evidence of a developing phenomenon in cancer research as it provides the first evidence of an emergent KRAS G12D/NF1 L1083R aberration with histological transformation occurring concurrently with primary BRAF V600E-altered glioblastoma as a previously unrecognized acquired mechanism of resistance in the setting of combined BRAF and MEK inhibition. This novel finding not only sheds new light on the RAS/MAPK pathway but also highlights the potential for morphological transformation to gliosarcoma, underscoring the critical need for further investigation in this area.

BRAF v600E-mutant cancers treated with vemurafenib alone or in combination with everolimus, sorafenib, or crizotinib or with paclitaxel and carboplatin (VEM-PLUS) study.

Combined BRAF + MEK inhibition is FDA approved for BRAF V600E-mutant solid tumors except for colorectal cancer. However, beyond MAPK mediated resistance several other mechanisms of resistance such as activation of CRAF, ARAF, MET, P13K/AKT/mTOR pathway exist among other complex pathways. In the VEM-PLUS study, we performed a pooled analysis of four phase one studies evaluating the safety and efficacy of vemurafenib monotherapy and vemurafenib combined with targeted therapies (sorafenib, crizotinib, or everolimus) or carboplatin plus paclitaxel in advanced solid tumors harboring BRAF V600 mutations. When vemurafenib monotherapy was compared with the combination regimens, no significant differences in OS or PFS durations were noted, except for inferior OS in the vemurafenib and paclitaxel and carboplatin trial (P = 0.011; HR, 2.4; 95% CI, 1.22-4.7) and in crossover patients (P = 0.0025; HR, 2.089; 95% CI, 1.2-3.4). Patients naïve to prior BRAF inhibitors had statistically significantly improved OS at 12.6 months compared to 10.4 months in the BRAF therapy refractory group (P = 0.024; HR, 1.69; 95% CI 1.07-2.68). The median PFS was statistically significant between both groups, with 7 months in the BRAF therapy naïve group compared to 4.7 months in the BRAF therapy refractory group (P = 0.016; HR, 1.80; 95% CI 1.11-2.91). The confirmed ORR in the vemurafenib monotherapy trial (28%) was higher than that in the combination trials. Our findings suggest that, compared with vemurafenib monotherapy, combinations of vemurafenib with cytotoxic chemotherapy or with RAF- or mTOR-targeting agents do not significantly extend the OS or PFS of patients who have solid tumors with BRAF V600E mutations. Gaining a better understanding of the molecular mechanisms of BRAF inhibitor resistance, balancing toxicity and efficacy with novel trial designs are warranted.

Spectrum of Immune Checkpoint Inhibitor Anemias: Results From a Single Center, Early-Phase Clinical Trials Case Series Experience.

Immune checkpoint inhibitor anemias (ICI-A) are a rare entity which can be potentially life-threatening without prompt identification. The goal of the study is to characterize the presentation, evaluation, and outcomes of ICI therapy in early phase clinical trial setting to guide future research and to develop standardized care guidelines. Retrospective chart review of 333 patients who participated in early phase clinical trials at the University of Texas MD Anderson Cancer Center revealed four cases with ICI-A between 2016 and 2020. We identified a spectrum of four cases which included ICI-related autoimmune hemolytic anemias, hemophagocytic lymphohistiocytosis and thrombotic microangiopathy as a result of combinatory investigational therapies involving ICI. Patient presentation, evaluation, bone marrow pathology, interventions, and clinical course were reviewed. The median time to onset of hematological immune-related adverse events (heme-irAEs) in this retrospective series was 3.5 weeks (2 - 6 weeks). One patient had pre-existing untreated chronic lymphocytic leukemia. Glucocorticoids are an effective first-line treatment in most patients although most patients were not rechallenged but successfully had complete recovery and pursued further non-immunotherapy-based therapies. Cognizance of ICI-A in clinical trial setting is paramount to early recognition of heme-irAEs. Further research is needed to identify and stratify risk factors during clinical trial enrollment and optimal management strategies for immune-mediated hematologic toxicities.

Elucidation of Novel Molecular Targets for Therapeutic Strategies in Urothelial Carcinoma: A Literature Review.

Urothelial carcinoma therapy is a rapidly evolving and expanding field. Traditional cytotoxic chemotherapy regimens have not produced optimal long-term outcomes, and many urothelial cancer patients have comorbidities that disqualify them as chemotherapy candidates. In recent years, a plethora of novel therapeutic agents that target diverse molecular pathways has emerged as alternative treatment modalities for not only metastatic urothelial carcinoma, but also for muscle-invasive bladder cancer and non-muscle invasive bladder cancer in adjuvant and definitive settings. This review paper aims to discuss the various categories of therapeutic agents for these different types of urothelial cancer, discussing immunotherapy, antibody-drug conjugates, kinase inhibitors, CAR-T cell therapy, peptide vaccination, and other drugs targeting pathways such as angiogenesis, DNA synthesis, mTOR/PI3K/AKT, and EGFR/HER-2.

Early Onset Neutropenia due to Rituximab Therapy in Mantle Cell Lymphoma: A Case Report.

Cases of late onset neutropenia (LON) after rituximab therapy have been documented, but few cases have been documented of early onset neutropenia (EON). We present a case report of a patient with mantle cell lymphoma who presented with EON, only 6 days after initiation of rituximab therapy, notable for the shortest duration to EON ever reported in literature. Throughout this paper, we explore the potential pathogenesis and incidence of EON with the help of our unique case.

Standard-Dose Rituximab as Effective Therapy for Treating Malignancy-Related Hemophagocytic Lymphohistiocytosis in the Eldery: A Case Report.

Hemophagocytic lymphohistiocytosis (HLH) is a syndrome involving uncontrolled inflammation due to widespread activation of immune response. HLH can be inherited or acquired secondary to infection, autoimmune, or oncologic processes such as small lymphocytic lymphoma (SLL) or chronic lymphocytic leukemia (CLL). There has been minimal documentation of HLH secondary to SLL/CLL, and results of treatment have been largely unsuccessful. This case describes a critically ill elderly patient with HLH caused by SLL/CLL who was successfully treated with standard-dose rituximab and regained a high quality of life.

Non-neoplastic inflammatory pseudotumor of the lung after immunotherapy for melanoma: A diagnostic pitfall on fine needle aspiration biopsy of lung.

Nivolumab is commonly used as monotherapy or in combination therapy for management of locally advanced or metastatic melanoma; however, it is also associated with immunotherapy-related adverse events concerning for disease progression or tumor flare reaction. This report presents a case of a non-neoplastic pseudotumor of the lung initially mistaken for malignancy that occurred in a patient receiving adjuvant nivolumab therapy following complete resection of stage IIIB melanoma. The diagnosis was made by lung biopsy and confirmed by a wedge resection, with findings consistent with organizing pneumonia type of pulmonary inflammatory pseudotumor rather than malignancy.

A unique case of hemolytic-uremic syndrome secondary to enteropathogenic E Coli.

Causative factors of HUS due to infection are not limited to classic EHEC and Shigella infection. Understanding the effects of EPEC-related HUS and its complications is imperative for early diagnosis and treatment to mitigate long-term sequelae.