Intravitreal fasudil monotherapy for treatment of refractory diabetic macular edema: A prospective interventional case series

BACKGROUND

Suboptimal response to conventional treatments in refractory diabetic macular edema (rDME) encourages efforts to identify new therapeutic options.

PURPOSE

To evaluate the effect of three monthly intravitreal injections of a Rho-associated protein kinase (ROCK) inhibitor (Fasudil, Asahi Kasei Pharma Corporation, Tokyo, Japan) in eyes with rDME.

METHODS

Ten eyes of 10 patients with DME unresponsive to at least six previous intravitreal bevacizumab (IVB) injections were recruited and underwent 3 consecutive monthly intravitreal injection of 0.025mg/0.05mL Fasudil. Best-corrected visual acuity (BCVA) and central macular thickness (CMT) were evaluated as functional and anatomical response indicators, respectively.

RESULTS

The mean age was 60.1±5.1 years (range, 53-68). Five cases responded to treatment, two with both anatomical and functional responses (reduction of CMT from 521 to 395 and from 390 to 301 microns and improvement of BCVA from 0.3 to 0.1 LogMAR and 0.6 to 0.4 LogMAR, respectively) and three with only functional improvement (0.7 to 0.4; 0.7 to 0.4; and 0.3 to 0.1 LogMAR). Of note, cases with no significant change in CMT showed morphologic improvement of the retinal microstructure to some extent. No adverse event was observed during the study period.

CONCLUSION

Monotherapy with intravitreal injection of ROCK inhibitors appears to have moderate visual benefits in eyes with DME refractory to IVB. Such effects may be functionally significant without obvious anatomical improvement.

Addendum to the German Consensus Recommendations on Ponatinib in the Treatment of Chronic Myeloid Leukemia

BACKGROUND

Based on the new data from the primary analysis of the OPTIC (Optimizing Ponatinib Treatment in CP-CML) trial on dose optimization of ponatinib in patients with chronic phase (CP)-CML, the German consensus paper on ponatinib published in 2020 (Saussele S et al., Acta Haematol. 2020) has been updated in this addendum.

SUMMARY

Focus is on the update of efficacy and safety of ponatinib, reflecting the new data set, as well as the update of the benefit-risk assessment and recommendations for ponatinib starting dose in CP-CML - provided that the decision to use ponatinib has already been made. Furthermore, based on OPTIC and additional empirical data, the expert panel collaborated to develop a decision tree for ponatinib dosing, specifically for intolerant and resistant patients. The recommendations on cardiovascular management have also been updated based on the most recent 2021 guidelines of the European Society of Cardiology (ESC) on cardiovascular disease prevention in clinical practice.

KEY MESSAGES

The OPTIC data confirm the high efficacy of ponatinib in patients with CP-CML and provide the basis for individualized dose adjustment during the course of treatment.

A real-world analysis of trametinib in combination with hydroxychloroquine or CDK4/6 inhibitor as third- or later-line therapy in metastatic pancreatic adenocarcinoma

BACKGROUND

There are no standard third-line treatment options for metastatic pancreatic ductal adenocarcinoma (mPDAC). Trametinib in combination with hydroxychloroquine (HCQ) or CDK4/6 inhibitors for pancreatic adenocarcinoma showed promising efficacy in preclinical studies. However, the regimens have not been well examined in patients with mPDAC.

METHODS

Patients with mPDAC who received the combination of trametinib and HCQ or CDK4/6 inhibitors as third- or later-line therapy were reviewed. The efficacy and prognosis were further analyzed.

RESULTS

A total of 13 mPDAC patients were enrolled, of whom 8 and 5 patients were treated with trametinib plus HCQ or a CDK4/6 inhibitor (palbociclib or abemaciclib), respectively. All enrolled patients had either KRAS G12D or G12V mutations and had received a median of 3 prior lines of therapy (range, 2-6). The median trametinib treatment duration was 1.4 months. Of the 10 patients with measurable disease, only 1 patient achieved stable disease, and the remaining patients had progressive disease. Moreover, in patients treated with trametinib plus HCQ and a CDK4/6 inhibitor, the median progression-free survival was 2.0 and 2.8 months, respectively, and the median overall survival was 4.2 and 4.7 months, respectively. Moreover, 5 (50%) patients experienced grade 3-4 adverse events in 10 patients with available safety data.

CONCLUSIONS

The combination of trametinib and HCQ or CDK4/6 inhibitors may not be an effective later-line treatment for mPDAC, and the current preliminary findings need to be confirmed by other studies with larger sample sizes.

Phase 1 study to evaluate the effects of rifampin or itraconazole on the pharmacokinetics of limertinib (ASK120067), a novel mutant-selective inhibitor of the epidermal growth factor receptor in healthy Chinese subjects

BACKGROUND

Limertinib is a novel mutant-selective and irreversible inhibitor of the epidermal growth factor receptor under development. A phase 1 open, two-period, single-sequence, self-controlled, two-part study was initiated to characterize the effects of a strong CYP3A4 inducer (rifampin) or inhibitor (itraconazole) on the pharmacokinetics of limertinib.

RESEARCH DESIGN AND METHODS

Twenty-four healthy subjects in each part received a single dose of limertinib alone (160 mg, Part A; 80 mg, Part B) and with multiple doses of rifampin 600 mg once daily (Part A) or itraconazole 200 mg twice daily (Part B).

RESULTS

Coadministration of rifampin decreased exposure (area under the plasma concentration-time curve from time 0 to infinity, AUC0-inf) of limertinib and its active metabolite CCB4580030 by 87.86% (geometric least-squares mean [GLSM] ratio, 12.14%; 90% confidence interval [CI], 9.89-14.92) and 66.82% (GLSM ratio, 33.18%; 90% CI, 27.72-39.72), respectively. Coadministration of itraconazole increased the AUC0-inf of limertinib by 289.8% (GLSM ratio, 389.8%; 90% CI, 334.07-454.82), but decreased that of CCB4580030 by 35.96% (GLSM ratio, 64.04%; 90% CI, 50.78-80.77).

CONCLUSIONS

Our study demonstrates that the concomitant use of limertinib with strong CYP3A inducers or inhibitors is not recommended. A single dose of limertinib, administered with or without rifampin or itraconazole, is generally safe and well tolerated in healthy Chinese subjects.

CLINICAL TRIAL REGISTRATION

www.clinicaltrials.gov identifier is NCT05631678.

Osimertinib and Selpercatinib Efficacy, Safety, and Resistance in a Multicenter, Prospectively Treated Cohort of EGFR-Mutant and RET Fusion-Positive Lung Cancers

PURPOSE

Acquired RET fusions have been reported at resistance to treatment with EGFR inhibitors in EGFR-mutant non-small cell lung cancer (NSCLC); however, a multicenter cohort of patients with EGFR-mutant lung cancers treated with osimertinib and selpercatinib for RET fusion-mediated osimertinib resistance has not previously been published.

PATIENTS AND METHODS

Patients who received selpercatinib in combination with osimertinib on a prospective expanded access clinical trial (NCT03906331) and single-patient compassionate use programs across five countries were centrally analyzed. All patients had advanced EGFR-mutant NSCLC with a RET fusion detected from tissue or plasma following osimertinib therapy. Clinicopathologic and outcomes data were collected.

RESULTS

Fourteen patients with EGFR-mutant and RET fusion-positive lung cancers who experienced prior progression on osimertinib received osimertinib and selpercatinib. EGFR exon 19 deletions (±T790M, 86%) and non-KIF5B fusions (CCDC6-RET 50%, NCOA4-RET 36%) predominated. Osimertinib 80 mg daily and selpercatinib 80 mg twice daily were the most commonly administered dosages. The response rate, disease control rate, and median treatment duration were 50% [95% confidence interval (CI), 25%-75%, n = 12], 83% (95% CI, 55%-95%), and 7.9 months (range, 0.8-25+), respectively. Resistance was complex, involving EGFR on-target (EGFR C797S), RET on-target (RET G810S), and off-target (EML4-ALK/STRN-ALK, KRAS G12S, BRAF V600E) mechanisms; RET fusion loss; or polyclonal mechanisms.

CONCLUSIONS

For patients with EGFR-mutant NSCLC with an acquired RET fusion as a mechanism of EGFR inhibitor resistance, the addition of selpercatinib to osimertinib was feasible and safe and offered clinical benefit, supporting the prospective evaluation of this combination. See related commentary by Krebs and Popat, p. 2951.

Randomized Phase II Trial of Sunitinib or Cediranib in Alveolar Soft Part Sarcoma

PURPOSE

Alveolar soft part sarcoma (ASPS) is a rare, highly vascular tumor with few treatment options. We designed a phase II randomized trial to determine the activity and tolerability of single-agent cediranib or sunitinib in patients with advanced metastatic ASPS.

PATIENTS AND METHODS

Patients 16 years of age and older were randomized to receive cediranib (30 mg) or sunitinib (37.5 mg) in 28-day cycles. Patients could cross over to the other treatment arm at disease progression. The primary endpoint was to measure the objective response rate (ORR) for each agent. Median progression-free survival (mPFS) for the two arms was also determined.

RESULTS

Twenty-nine of 34 enrolled patients were evaluable for response. One patient on each of the initial two treatment arms had a partial response (ORR: 6.7% and 7.1% for cediranib and sunitinib, respectively). Twenty-four patients had a best response of stable disease (86.7% and 78.6% for cediranib and sunitinib, respectively). There were no significant differences in mPFS for the two treatment arms. Clinical benefit (i.e., objective response or stable disease for a minimum of four or six cycles of therapy) on the first-line tyrosine kinase inhibitor (TKI) therapy did not predict benefit on the second-line TKI. Both drugs were well tolerated. As of August 2021, 1 patient (unevaluable for ORR) remains on study.

CONCLUSIONS

The study did not meet its endpoints for ORR. Although both TKIs provided clinical benefit, the outcomes may have been attenuated in patients who had progressed ≤6 months before enrollment, potentially accounting for the low response rates. See related commentary by Wilky and Maleddu, p. 1163.

Development of Furanopyrimidine-Based Orally Active Third-Generation EGFR Inhibitors for the Treatment of Non-Small Cell Lung Cancer

The development of orally bioavailable, furanopyrimidine-based double-mutant (L858R/T790M) EGFR inhibitors is described. First, selectivity for mutant EGFR was accomplished by replacing the (S)-2-phenylglycinol moiety of 12 with either an ethanol or an alkyl substituent. Then, the cellular potency and physicochemical properties were optimized through insights from molecular modeling studies by implanting various solubilizing groups in phenyl rings A and B. Optimized lead 52 shows 8-fold selective inhibition of H1975 (EGFR^L858R/T790M overexpressing) cancer cells over A431 (EGFR^WT overexpressing) cancer cells; western blot analysis further confirmed EGFR mutant-selective target modulation inside the cancer cells by 52. Notably, 52 displayed in vivo antitumor effects in two different mouse xenograft models (BaF3 transfected with mutant EGFR and H1975 tumors) with TGI = 74.9 and 97.5% after oral administration (F = 27%), respectively. With an extraordinary kinome selectivity (S(10) score of 0.017), 52 undergoes detailed preclinical development.

Ibrutinib plus Bendamustine and Rituximab in Untreated Mantle-Cell Lymphoma

BACKGROUND

Ibrutinib, a Bruton's tyrosine kinase inhibitor, may have clinical benefit when administered in combination with bendamustine and rituximab and followed by rituximab maintenance therapy in older patients with untreated mantle-cell lymphoma.

METHODS

We randomly assigned patients 65 years of age or older to receive ibrutinib (560 mg, administered orally once daily until disease progression or unacceptable toxic effects) or placebo, plus six cycles of bendamustine (90 mg per square meter of body-surface area) and rituximab (375 mg per square meter). Patients with an objective response (complete or partial response) received rituximab maintenance therapy, administered every 8 weeks for up to 12 additional doses. The primary end point was progression-free survival as assessed by the investigators. Overall survival and safety were also assessed.

RESULTS

Among 523 patients, 261 were randomly assigned to receive ibrutinib and 262 to receive placebo. At a median follow-up of 84.7 months, the median progression-free survival was 80.6 months in the ibrutinib group and 52.9 months in the placebo group (hazard ratio for disease progression or death, 0.75; 95% confidence interval, 0.59 to 0.96; P = 0.01). The percentage of patients with a complete response was 65.5% in the ibrutinib group and 57.6% in the placebo group (P = 0.06). Overall survival was similar in the two groups. The incidence of grade 3 or 4 adverse events during treatment was 81.5% in the ibrutinib group and 77.3% in the placebo group.

CONCLUSIONS

Ibrutinib treatment in combination with standard chemoimmunotherapy significantly prolonged progression-free survival. The safety profile of the combined therapy was consistent with the known profiles of the individual drugs. (Funded by Janssen Research and Development and Pharmacyclics; SHINE ClinicalTrials.gov number, NCT01776840.).

ASCEND-7: Efficacy and Safety of Ceritinib Treatment in Patients with ALK-Positive Non-Small Cell Lung Cancer Metastatic to the Brain and/or Leptomeninges

PURPOSE

Central nervous system metastases are a prominent cause of morbidity and mortality in patients with ALK-positive (ALK+) non-small cell lung cancer (NSCLC). The phase II ASCEND-7 (NCT02336451) study was specifically designed to assess the efficacy and safety of the ALK inhibitor (ALKi) ceritinib in patients with ALK+ NSCLC metastatic to the brain and/or leptomeninges.

PATIENTS AND METHODS

Patients with active brain metastases were allocated to study arms 1 to 4 based on prior exposure to an ALKi and/or prior brain radiation (arm 1: prior radiotherapy/ALKi-pretreated; arm 2: no radiotherapy/ALKi-pretreated; arm 3: prior radiotherapy/ALKi-naïve; arm 4: no radiotherapy/ALKi-naïve). Arm 5 included patients with leptomeningeal carcinomatosis. Patients received ceritinib 750 mg once daily (fasted condition). Primary endpoint was investigator-assessed whole-body overall response rate (ORR) per RECIST v1.1. Secondary endpoints included disease control rate (DCR) and intracranial/extracranial responses.

RESULTS

Per investigator assessment, in arms 1 (n = 42), 2 (n = 40), 3 (n = 12), and 4 (n = 44), respectively: whole-body ORRs [95% confidence interval (CI)] were 35.7% (21.6-52.0), 30.0% (16.6-46.5), 50.0% (21.1-78.9), and 59.1% (43.2-73.7); whole-body DCR (95% CI): 66.7% (50.5-80.4), 82.5% (67.2-92.7), 66.7% (34.9-90.1), and 70.5% (54.8-83.2); intracranial ORRs (95% CI): 39.3% (21.5-59.4), 27.6% (12.7-47.2), 28.6% (3.7-71.0), and 51.5% (33.5-69.2). In arm 5 (n = 18), whole-body ORR was 16.7% (95% CI, 3.6-41.4) and DCR was 66.7% (95% CI, 41.0-86.7). Paired cerebrospinal fluid and plasma sampling revealed that ceritinib penetrated the human blood-brain barrier.

CONCLUSIONS

Ceritinib showed antitumor activity in patients with ALK+ NSCLC with active brain metastases and/or leptomeningeal disease, and could be considered in the management of intracranial disease. See related commentary by Murciano-Goroff et al., p. 2477.

Rilzabrutinib, an Oral BTK Inhibitor, in Immune Thrombocytopenia

BACKGROUND

Rilzabrutinib, an oral, reversible covalent inhibitor of Bruton's tyrosine kinase, may increase platelet counts in patients with immune thrombocytopenia by means of dual mechanisms of action: decreased macrophage (Fcγ receptor)-mediated platelet destruction and reduced production of pathogenic autoantibodies.

METHODS

In an international, adaptive, open-label, dose-finding, phase 1-2 clinical trial, we evaluated rilzabrutinib therapy in previously treated patients with immune thrombocytopenia. We used intrapatient dose escalation of oral rilzabrutinib over a period of 24 weeks; the lowest starting dose was 200 mg once daily, with higher starting doses of 400 mg once daily, 300 mg twice daily, and 400 mg twice daily. The primary end points were safety and platelet response (defined as at least two consecutive platelet counts of ≥50×10³ per cubic millimeter and an increase from baseline of ≥20×10³ per cubic millimeter without the use of rescue medication).

RESULTS

Sixty patients were enrolled. At baseline, the median platelet count was 15×10³ per cubic millimeter, the median duration of disease was 6.3 years, and patients had received a median of four different immune thrombocytopenia therapies previously. All the treatment-related adverse events were of grade 1 or 2 and transient. There were no treatment-related bleeding or thrombotic events of grade 2 or higher. At a median of 167.5 days (range, 4 to 293) of treatment, 24 of 60 patients (40%) overall and 18 of the 45 patients (40%) who had started rilzabrutinib treatment at the highest dose met the primary end point of platelet response. The median time to the first platelet count of at least 50×10³ per cubic millimeter was 11.5 days. Among patients with a primary platelet response, the mean percentage of weeks with a platelet count of at least 50×10³ per cubic millimeter was 65%.

CONCLUSIONS

Rilzabrutinib was active and associated with only low-level toxic effects at all dose levels. The dose of 400 mg twice daily was identified as the dose for further testing. Overall, rilzabrutinib showed a rapid and durable clinical activity that improved with length of treatment. (Funded by Sanofi; ClinicalTrials.gov number, NCT03395210; EudraCT number, 2017-004012-19.).

The tyrosine kinase inhibitor LPM4870108 impairs learning and memory and induces transcriptomic and gene‑specific DNA methylation changes in rats

Tyrosine kinase inhibitors (TKIs), which have been developed and approved for cancer treatment in the last few years, are involved in synaptic plasticity of learning and memory. Epigenetic modifications also play crucial roles in the process of learning and memory, but its relationship with TKI-induced learning and memory impairment has not been investigated. We hypothesized that LPM4870108, an effective anti-cancer Trk inhibitor, might affect the learning and memory via epigenetic modifications. In this study, rats were orally administered with LPM4870108 (0, 1.25, 2.5, or 5.0 mg/kg) twice daily for 28 days, after which animals were subjected to a Morris water maze test. LPM4870108 exposure caused learning and memory impairments in this test in a dose-dependent manner and reduced the spine densities. Whole-genome transcriptomic analysis revealed significant differences in the patterns of hippocampal gene expression in LPM4870108-treated rats. These transcriptomic data were combined with next-generation bisulfite sequencing analysis, after which RT-PCR and pyrosequencing were conducted, revealing epigenetic alterations associated with genes (Snx8, Fgfr1, Dusp4, Vav2, and Satb2) known to regulate learning and memory. Increased mRNA and protein expression levels of hippocampal Dnmt1 and Dnmt3a were also observed in these rats. Overall, these data suggest that gene-specific alterations in patterns of DNA methylation can potentially contribute to the incidence of learning and memory deficits associated with exposure to LPM4870108.

CaboPoint: a phase II study of cabozantinib as second-line treatment in patients with metastatic renal cell carcinoma

Cabozantinib is an inhibitor of multiple tyrosine kinases, including AXL, MET and VEGF receptors. Here, we describe the rationale and design for the phase II CaboPoint trial (ClinicalTrials.gov identifier: NCT03945773), which will evaluate the efficacy and safety of cabozantinib as a second-line treatment in patients with unresectable, locally advanced or metastatic renal cell carcinoma whose disease has progressed despite checkpoint inhibitor therapy. Patients will be recruited into two cohorts: prior ipilimumab plus nivolumab (cohort A) or prior checkpoint inhibitor-VEGF-targeted therapy (cohort B). All patients will receive once-daily oral cabozantinib 60 mg for up to 18 months. The primary end point is objective response rate. Secondary end points include overall survival, progression-free survival and safety.

The Efficacy and Safety of Anlotinib Alone and in Combination with Other Drugs in Advanced Lung Cancer: A Retrospective Cohort Study

OBJECTIVE

Lung cancer is a disease associated with high levels of morbidity and mortality, with approximately 2.1 million new cases every year. Anlotinib is a new small-molecule multitarget tyrosine kinase inhibitor independently developed in China that can inhibit the formation of tumor blood vessels and has a therapeutic effect on various cancers. However, the application of anlotinib in lung cancer needs further investigation.

METHODS

We collected the progress notes of 43 patients with advanced lung cancer treated at the Oncology Department of Guangzhou Chest Hospital from March 2019 to March 2021. Additionally, we assessed the differences between drug combination therapy and single-drug therapy among patients treated with anlotinib.

RESULTS

Patients in both the anlotinib-combination and anlotinib-monotherapy groups experienced remission; however, the overall disease control rate in the anlotinib-combination group was higher than that in the anlotinib-monotherapy group. Reexamination via computed tomography showed that patients in the anlotinib-combination group had better recovery than those in the anlotinib-monotherapy group. Although the overall incidence of adverse reactions in the anlotinib-combination group was higher than that in the monotherapy group, most of the adverse reactions were I-II levels and improved after symptomatic treatment.

CONCLUSION

Anlotinib combined with other therapies is better than anlotinib alone for the management of patients with advanced lung cancer.

A Randomized Study of Lenvatinib 18 mg vs 24 mg in Patients With Radioiodine-Refractory Differentiated Thyroid Cancer

BACKGROUND

Lenvatinib is a multikinase inhibitor approved to treat radioiodine-refractory differentiated thyroid cancer (RR-DTC) at a starting dose of 24 mg/day. This study explored, in a double-blinded fashion, whether a starting dose of 18 mg/day would provide comparable efficacy with reduced toxicity.

METHODS

Patients with RR-DTC were randomized to lenvatinib 24 mg/day or 18 mg/day. The primary efficacy endpoint was objective response rate as of week 24 (ORRwk24); the odds ratio noninferiority margin was 0.4. The primary safety endpoint was frequency of grade ≥3 treatment-emergent adverse events (TEAEs) as of week 24. Tumors were assessed using RECIST v1.1. TEAEs were monitored and recorded.

RESULTS

The ORRwk24 was 57.3% (95% CI 46.1, 68.5) in the lenvatinib 24-mg arm and 40.3% (95% CI 29.3, 51.2) in the lenvatinib 18-mg arm, with an odds ratio (18/24 mg) of 0.50 (95% CI 0.26, 0.96). As of week 24, the rates of TEAEs grade ≥3 were 61.3% in the lenvatinib 24-mg arm and 57.1% in the lenvatinib 18-mg arm, a difference of -4.2% (95% CI -19.8, 11.4).

CONCLUSION

A starting dose of lenvatinib 18 mg/day did not demonstrate noninferiority compared to a starting dose of 24 mg/day as assessed by ORRwk24 in patients with RR-DTC. The results represent a clinically meaningful difference in ORRwk24. The safety profile was comparable, with no clinically relevant difference between arms. These results support the continued use of the approved starting dose of lenvatinib 24 mg/day in patients with RR-DTC and adjusting the dose as necessary.

Integrated Molecular Characterization of Patient-Derived Models Reveals Therapeutic Strategies for Treating CIC-DUX4 Sarcoma

Capicua-double homeobox 4 (CIC-DUX4)-rearranged sarcomas (CDS) are extremely rare, highly aggressive primary sarcomas that represent a major therapeutic challenge. Patients are treated according to Ewing sarcoma protocols, but CDS-specific therapies are strongly needed. In this study, RNA sequencing was performed on patient samples to identify a selective signature that differentiates CDS from Ewing sarcoma and other fusion-driven sarcomas. This signature was used to validate the representativeness of newly generated CDS experimental models-patient-derived xenografts (PDX) and PDX-derived cell lines-and to identify specific therapeutic vulnerabilities. Annotation analysis of differentially expressed genes and molecular gene validation highlighted an HMGA2/IGF2BP/IGF2/IGF1R/AKT/mTOR axis that characterizes CDS and renders the tumors particularly sensitive to combined treatments with trabectedin and PI3K/mTOR inhibitors. Trabectedin inhibited IGF2BP/IGF2/IGF1R activity, but dual inhibition of the PI3K and mTOR pathways was required to completely dampen downstream signaling mediators. Proof-of-principle efficacy for the combination of the dual AKT/mTOR inhibitor NVP-BEZ235 (dactolisib) with trabectedin was obtained in vitro and in vivo using CDS PDX-derived cell lines, demonstrating a strong inhibition of local tumor growth and multiorgan metastasis. Overall, the development of representative experimental models (PDXs and PDX-derived cell lines) has helped to identify the unique sensitivity of the CDS to AKT/mTOR inhibitors and trabectedin, revealing a mechanism-based therapeutic strategy to fight this lethal cancer.

SIGNIFICANCE

This study identifies altered HMGA2/IGF2BP/IGF2 signaling in CIC-DUX4 sarcomas and provides proof of principle for combination therapy with trabectedin and AKT/mTOR dual inhibitors to specifically combat the disease.

Dose-dependent bioavailability and tissue distribution of the ATR inhibitor AZD6738 (ceralasertib) in mice

PURPOSE

Ataxia telangiectasia and Rad3-related (ATR) initiates and regulates cellular responses to DNA damage, such as those caused by cancer treatments. Several ATR inhibitors (ATRi) are in clinical development including AZD6738. Therapeutic indices among ATRi may differ as a result of varying potencies and concentrations at both tumor and off-target sites. Additionally, AZD6738 contributes to anti-tumor immune responses necessitating evaluation of exposure at immunological sites.

METHODS

Using mouse models and a highly sensitive LC-MS/MS assay, the pharmacokinetics of AZD6738 were studied, including dose linearity, bioavailability, metabolism, and tissue distribution in tumor-bearing mice.

RESULTS

Initial studies identified dose-dependent bioavailability, with greater than proportional increases in exposure as dose increased resulting in a ~ twofold increase in bioavailability between the lowest and highest investigated doses. These behaviors were successfully captured with a compartmental PK model. Analysis of metabolite PK revealed decreasing metabolic ratios with increasing dose, indicative of saturable first-pass metabolism. Further analysis revealed that intestinal and gut metabolism contribute to metabolism and these saturable mechanisms. Studies of tumor and tissue distribution found rapid and extensive drug distribution to most tissues except brain and spinal cord.

CONCLUSION

The complex non-linear behavior of AZD6738 PK in mice was due to pre-systemic saturation and which appears to be recapitulated clinically at low doses. PK reported here will allow future correlation of tissue related toxicities with drug exposure as well as exposure with immunological responses. These results can also be compared with those from similar studies of other ATRi to contrast drug exposure with responses.

Targeting DNMT1 by demethylating agent OR-2100 increases tyrosine kinase inhibitors-sensitivity and depletes leukemic stem cells in chronic myeloid leukemia

ABL1 tyrosine kinase inhibitors (TKIs) dramatically improve the prognosis of chronic myeloid leukemia (CML), but 10-20% of patients achieve suboptimal responses with low TKIs sensitivity. Furthermore, residual leukemic stem cells (LSCs) are involved in the molecular relapse after TKIs discontinuation. Aberrant DNA hypermethylation contributes to low TKIs sensitivity and the persistence of LSCs in CML. DNMT1 is a key regulator of hematopoietic stem cells, suggesting that aberrant DNA hypermethylation targeting DNMT1 represents a potential therapeutic target for CML. We investigated the efficacy of OR-2100 (OR21), the first orally available single-compound prodrug of decitabine. OR21 exhibited anti-tumor effects as a monotherapy, and in combination therapy it increased TKI-induced apoptosis and induction of tumor suppressor genes including PTPN6 encoding SHP-1 in CML cells. OR21 in combination with imatinib significantly suppressed tumor growth in a xenotransplant model. OR21 and combination therapy decreased the abundance of LSCs and inhibited engraftment in a BCR-ABL1-transduced mouse model. These results demonstrate that targeting DNMT1 using OR21 exerts anti-tumor effects and impairs LSCs in CML. Therefore, combination treatment of TKIs and OR21 represents a promising treatment strategy in CML.

Thyroid autoimmunity and hypothyroidism are associated with deep molecular response in patients with chronic myeloid leukemia on tyrosine kinase inhibitors

PURPOSE

Thyroid alterations including de novo appearance of thyroid autoimmunity are adverse effects of tyrosine kinase inhibitors, used in solid and hematologic cancer therapy, but the relationship between thyroid alterations during this treatment and the outcome of chronic myeloid leukemia remains unclear. Aim of this study was to investigate whether the presence of thyroid alterations may affect the clinical outcome of chronic myeloid leukemia on tyrosine kinase inhibitors.

METHODS

We evaluated thyroid function and autoimmunity in 69 chronic myeloid leukemia patients on long-term therapy looking at the association between thyroid abnormalities and disease molecular response.

RESULTS

Overall, 24 of 69 (34.8%) had one or more thyroid abnormalities during therapy. A high percentage of patients (21/69, 30.4%) showed thyroid autoimmunity (positive thyroid autoantibodies with ultrasound hypoechogenicity), while clinical and subclinical hypothyroidism and subclinical hyperthyroidism were, respectively, found in 4 of 69 (5.8%) and 3 of 69 (4.3%) of cases. Second-generation tyrosine kinase inhibitors resulted significantly associated (14/32, 43.7%) with Hashimoto's thyroiditis, compared to first generation (7/37, 18.9%; p = 0.03). Interestingly, we also found a significant association between euthyroid (14/26, 53.8%) and hypothyroid Hashimoto's thyroiditis (4/26, 15.4%) in patients with deep molecular response, as compared to euthyroid (3/43, 7%; p = 0.0001) and hypothyroid (0/43, 0%; p = 0.02) Hashimoto's thyroiditis patients with major molecular response.

CONCLUSIONS

Our study confirms and extends our knowledge on the tyrosine kinase inhibitors effects on thyroid, showing that thyroid autoimmunity is frequently observed in chronic myeloid leukemia patients on long-term therapy and is associated with a better oncological response.

Prognostic Significance of Platelet (PLT) and Platelet to Mean Platelet Volume (PLT/MPV) Ratio During Apatinib Second-Line or Late-Line Treatment in Advanced Esophageal Squamous Cell Carcinoma Patients

Background: Apatinib has a certain efficacy for advanced esophageal squamous cell carcinoma (ESCC). This study aimed to investigate the prognostic significance of platelet (PLT) and platelet to mean platelet volume (PLT/MPV) ratio for advanced ESCC patients with apatinib second-line or late-line treatment. Methods: A retrospective study included 80 patients with advanced ESCC who received Apatinib ≥ 2 lines targeted therapy. We collected baseline clinical characteristics and blood parameters from the patients. Kaplan-Meier plots and univariate and multivariate analysis were used to find the factors related to progression-free survival (PFS). Results: The optimal cut-off values of PLT and PLT/MPV ratio were determined by X-tile software. Kaplan-Meier analysis demonstrated that patients in the high PLT group had better PFS than those in the low PLT group (156 d vs 80 d, P <.001), and patients in the high PLT/MPV ratio group had better PFS than those in low PLT/MPV ratio group (157 d vs 85 d, P <.001). Univariate analysis revealed pretreatment PLT and PLT/MPV ratio were significantly correlated with PFS. Multivariate analysis revealed high levels of pretreatment PLT/MPV ratio was an independent predictor of longer PFS (HR: 0.257, 95% CI: 0.089-0.743, P = .012). Conclusion: High levels of baseline PLT and PLT/MPV may indicate a better prognosis in apatinib ≥ 2 lines treatment for advanced ESCC patients.

Exposure-response analyses of erdafitinib in patients with locally advanced or metastatic urothelial carcinoma

Background

Exposure–response analyses were conducted to explore the relationship between selected efficacy and safety endpoints and serum phosphate (PO4) concentrations, a potential biomarker of efficacy and safety, in locally advanced or metastatic urothelial carcinoma patients with FGFR alterations treated with erdafitinib.

Methods

Data from two dosing regimens of erdafitinib in a phase 2 study (NCT02365597), 6 and 8-mg/day with provision for pharmacodynamically guided titration per serum PO4 levels, were analyzed using Cox proportional hazard or logistic regression models. Efficacy endpoints were overall survival (OS), progression-free survival (PFS), and objective response rate (ORR). Safety endpoints were adverse events typical for FGFR inhibitors.

Results

Exposure-efficacy analyses on 156 patients (6-mg = 68; 8-mg = 88) showed that patients with higher serum PO4 levels within the first 6 weeks showed better OS (hazard ratio 0.57 [95% CI 0.46–0.72] per mg/dL of PO4; p = 0.01), PFS (hazard ratio 0.80 [0.67–0.94] per mg/dL of PO4; p = 0.01), and ORR (odds ratio 1.38 [1.02–1.86] per mg/dL of PO4; p = 0.04). Exposure-safety analyses on 177 patients (6-mg = 78; 8-mg = 99) showed that the incidence of selected adverse events associated with on-target off-tumor effects significantly rose with higher PO4.

Conclusions

The exploratory relationship between serum PO4 levels and efficacy/safety outcomes supported the use of pharmacodynamically guided dose titration to optimize erdafitinib’s therapeutic benefit/risk ratio.

Clinical trial registration number

NCT02365597.

Supplementary Information

The online version contains supplementary material available at 10.1007/s00280-021-04381-4.

The natural product berberine synergizes with osimertinib preferentially against MET-amplified osimertinib-resistant lung cancer via direct MET inhibition

Berberine is a natural product that has long been used in traditional Chinese medicine due to its antimicrobial, anti-inflammatory and metabolism-regulatory properties. Osimertinib is the first third-generation EGFR-tyrosine kinase inhibitor (TKI) approved for the treatment of non-small cell lung cancer (NSCLC) with activating EGFR mutations and those resistant to earlier generation EGFR-TKIs due to a T790M mutation. However, emergence of acquired resistance to osimertinib limits its long-term efficacy in the clinic. One known mechanism of acquired resistance to osimertinib and other EGFR-TKIs is MET (c-MET) gene amplification. Here, we report that berberine, when combined with osimertinib, synergistically and selectively decreased the survival of several MET-amplified osimertinib-resistant EGFR mutant NSCLC cell lines with enhanced induction of apoptosis likely through Bim elevation and Mcl-1 reduction. Importantly, this combination effectively enhanced suppressive effect on the growth of MET-amplified osimertinib-resistant xenografts in nude mice and was well tolerated. Molecular modeling showed that berberine was able to bind to the kinase domain of non-phosphorylated MET, occupy the front of the binding pocket, and interact with the activation loop, in a similar way as other known MET inhibitors do. MET kinase assay showed clear concentration-dependent inhibitory effects of berberine against MET activity, confirming its kinase inhibitory activity. These findings collectively suggest that berberine can act as a naturally-existing MET inhibitor to synergize with osimertinib in overcoming osimertinib acquired resistance caused by MET amplification.

Acquired Resistance Mechanism of EGFR Kinase Domain Duplication to EGFR TKIs in Non-Small Cell Lung Cancer

PURPOSE

Epidermal growth factor receptor kinase domain duplication (EGFR-KDD) is a rare and poorly understood oncogenic mutation in non-small cell lung cancer (NSCLC). We aimed to investigate the acquired resistance mechanism of EGFR-KDD against EGFR-TKIs.

MATERIALS AND METHODS

We identified EGFR-KDD in tumor tissue obtained from a patient with stage IV lung adenocarcinoma and established the patient-derived cell line SNU-4784. We also established several EGFR-KDD Ba/F3 cell lines: EGFR-KDD wild type (EGFR-KDDWT), EGFR-KDD domain 1 T790M (EGFR-KDDD1T), EGFR-KDD domain 2 T790M (EGFR-KDDD2T), and EGFR-KDD both domain T790M (EGFR-KDDBDT). We treated the cells with EGFR tyrosine kinase inhibitors (TKIs) and performed cell viability assays, immunoblot assays, and ENU (N-ethyl-N-nitrosourea) mutagenesis screening.

RESULTS

In cell viability assays, SNU-4784 cells and EGFR-KDDWT Ba/F3 cells were sensitive to 2nd generation and 3rd generation EGFR TKIs. In contrast, the T790M-positive EGFR-KDD Ba/F3 cell lines (EGFR-KDDT790M) were only sensitive to 3rd generation EGFR TKIs. In ENU mutagenesis screening, we identified the C797S mutation in kinase domain 2 of EGFR-KDDBDT Ba/F3 cells. Based on this finding, we established an EGFR-KDD domain 1 T790M/domain 2 cis-T790M+C797S (EGFR-KDDT/T+C) Ba/F3 model, which was resistant to EGFR TKIs and anti-EGFR monoclonal antibody combined with EGFR TKIs.

CONCLUSION

Our study reveals that the T790M mutation in EGFR-KDD confers resistance to 1st and 2nd generation EGFR TKIs, but is sensitive to 3rd generation EGFR TKIs. In addition, we identified that the C797S mutation in kinase domain 2 of EGFR-KDDT790M mediates a resistance mechanism against 3rd generation EGFR TKIs.

Clinical practice of epidermal growth factor receptor-tyrosine kinase inhibitor targeted drugs combined with gadolinium oxide nanoparticles in the treatment of non-small cell lung cancer

It was to explore the clinical efficacy and safety of epidermal growth factor receptor-tyrosine kinase inhibitor (EGFR-TKI) targeted drugs combined with hyaluronic acid-gadolinium sesquioxide-nanoparticles (HA-Gd2O3-NPs) in non-small cell lung cancer (NSCLC). In this study, 70 patients with stage IV EGFR mutant NSCLC diagnosed in the First Affiliated Hospital of Jinzhou Medical University were selected. They were randomly divided into the combined group (35 cases) and the control group (35 cases). HA-Gd2O3-NPs were prepared by hydrothermal polymerization, and combined with EGFR-TKI in the clinical treatment of NSCLC. The results showed that HA-Gd2O3-NPs were spherical with a uniform particle size of about 124 nm. The NSCLC survival rate of the combined group was 37.2 ± 5.3% under 6 Gy X-ray irradiation, and that of the control group was 98.4 ± 12.6% under 6 Gy X-ray irradiation. The total effective rate of the control group (20%) was significantly lower than that of the study group (42.86%) (P < 0.05). The one-year survival rate of the combined group (94%) was significantly higher than that of the control group (75%) (P < 0.05). The median progression-free survival (PFS) in the control group was 8 months, and that in the combined group was 12 months, with statistical difference (P < 0.05). EGFR-TKI targeted drugs combined with HA-Gd2O3-NPs can significantly improve the clinical efficacy of stage IV EGFR mutant NSCLC patients and benefit their survival.

New Indication for Cabozantinib

Cabozantinib (Cabometyx) is now approved to treat locally advanced or metastatic differentiated thyroid cancer that has progressed following prior vascular endothelial growth factor receptor-targeted therapy.

Melanoma trials that defined surgical management: Brief overview of current/upcoming adjuvant/neoadjuvant trials

Adjuvant systemic therapy for cutaneous melanoma has experienced practice-changing shifts over the last decade. The successful results of immunotherapies and targeted therapies in the metastatic setting have allowed for investigative trials of the same therapies in the adjuvant and now neoadjuvant setting, with the potential for improved clinical outcomes in patients with high risk resected Stage III and IV melanoma.