Pharmacokinetics of intravenous pan-class I phosphatidylinositol 3-kinase (PI3K) inhibitor [14C]copanlisib (BAY 80-6946) in a mass balance study in healthy male volunteers

Structure-based drug design, synthesis, and biological evaluation of novel 1,3,5-triazine or pyrimidine derivatives containing benzoyl hydrazine moiety as PI3Kα selective inhibitors

Phosphoinositide 3-kinase (PI3K) was an important cellular signal transducer, while PI3Kα was the most mutated family member in cancer. Selective PI3Kα inhibitors have become the frequent research in recent years because of their excellent curative effect and reduced side effects. Here, we described a series of PI3Kα inhibitors with 1,3,5-triazine or pyrimidine skeleton containing benzoyl hydrazine based on the pan-PI3K inhibitor ZSTK474 relying on the strategies of structure-based drug discovery (SBDD) and computer-aided drug design (CADD). Among them, compound F8 exhibited improved selective PI3Kα inhibition with an IC50 value of 0.14 nM and more significant anti-proliferative activities against three tumor-derived cell lines (PC-3 IC50 = 0.28 μM, HCT-116 IC50 = 0.57 μM, and U87-MG IC50 = 1.37 μM) than ZSTK-474. Compound F-8 induced a great decrease in mitochondrial membrane which caused cell cycle arrest at G1 phase and apoptosis in U87-MG cells in a dose-dependent manner. Furthermore, compound F8 induced significant tumor regressions in a xenograft mouse model of U87-MG cell line with no clear evidence of toxicity following intraperitoneal injection of 40 mg/kg. Compound F8 may serve as a PI3Kα-selective inhibitor and provided the opportunity to spare patients the side effects associated with broader inhibition of the class I PI3K family.

Model-informed approach to support pediatric dosing for the pan-PI3K inhibitor copanlisib in children and adolescents with relapsed/refractory solid tumors

Copanlisib is an intravenously administered phosphatidylinositol 3-kinase (PI3K) inhibitor which was investigated in pediatric patients with relapsed/refractory solid tumors. A model-informed approach was undertaken to support and confirm an empirically selected starting dose of 28 mg/m2 for pediatric patients ≥1 year old, corresponding to 80% of the adult recommended dose adjusted for body surface area. An adult physiologically based pharmacokinetic (PBPK) model was initially established using copanlisib physicochemical and disposition properties and clinical pharmacokinetics (PK) data and was shown to adequately capture clinical PK across a range of copanlisib doses in adult cancer patients. The adult PBPK model was then extended to the pediatric population through incorporation of age-dependent anatomical and physiological changes and used to simulate copanlisib exposures in pediatric cancer patient age groups. The pediatric PBPK model predicted that the copanlisib 28 mg/m2 dose would achieve similar copanlisib exposures across pediatric ages when compared with historical adult exposures following the approved copanlisib 60 mg dose administered on Days 1, 8, and 15 of a 28-day cycle. Clinical PK were collected from a phase I study in pediatric patients with relapsed/refractory solid tumors (aged ≥4 years). An established adult population PK model was extended to incorporate an allometrically-scaled effect of body surface area and confirmed that the copanlisib maximum tolerated dose of 28 mg/m2 was appropriate to achieve uniform copanlisib exposures across the investigated pediatric age range and consistent exposures to historical data in adult cancer patients. The model-informed approach successfully supported and confirmed the copanlisib pediatric dose recommendation.

Validated LC-MS/MS method for the determination of copanlisib in mouse dried blood spots

Copanlisib is a dual PI3K-δ inhibitor, used in follicular lymphoma treatment. In this research, we report a validated LC-MS/MS method for quantifying copanlisib from a mouse dried blood spot (DBS). We validated the method in line with the guidelines of the US Food and Drug Administration. The liquid-liquid extraction technique was used to extract copanlisib from the DBS discs. We used an Atlantis dC₁₈ column and isocratic mobile phase for the chromatographic separation of copanlisib and the internal standard (idelalisib). The flow was 0.90 ml/min. Under the optimized chromatographic conditions, the retentions of copanlisib and the internal standard were 0.98 and 0.93 min, respectively. Each injection total run time was 2.50 min. The MS/MS ion transitions monitored were m/z 481.31 → 128.00 and 416.10 → 176.10 for copanlisib and the internal standard (IS) idelalisib, respectively. We have used a broad calibration range (1.01-4,797 ng/ml) with a determination coefficient (r² ) of 0.997. All of the evaluated parameters met the acceptance criteria. Hematocrit did not influence the DBS copanlisib concentrations. We have used the validated method to derive the intravenous pharmacokinetic parameters by quantifying copanlisib in mouse plasma.

A phase I pharmacokinetic study of copanlisib in Chinese patients with relapsed indolent non-Hodgkin lymphoma

PURPOSE

Copanlisib, a pan-PI3K inhibitor, has previously shown clinical efficacy and a tolerable safety profile in patients with indolent non-Hodgkin lymphoma. However, the pharmacokinetics, safety, tolerability, and efficacy of copanlisib in Chinese patients have not been reported.

METHODS

This was a single-arm, open-label, phase I study of copanlisib in Chinese patients with relapsed or refractory indolent non-Hodgkin lymphoma (iNHL). Patients received a single intravenous 60 mg infusion of copanlisib over 1 h on days 1, 8, and 15 of a 28-day cycle, with 1 week of rest. Safety was monitored throughout the study, and plasma copanlisib levels were measured for pharmacokinetic analysis. Tumor response was determined by independent central radiologic review.

RESULTS

Sixteen patients were enrolled and 13 were treated with 60 mg of copanlisib for a median of 15.0 weeks. With a C_max of 566 μg/L and a AUC (0-24) of 1880 μg·h/L following single intravenous infusion, the pharmacokinetic parameters of copanlisib were consistent with that in previous studies, and no accumulation in plasma was observed. Treatment-emergent adverse events were reported for all 13 patients, the most common of which were hyperglycemia (100.0%), hypertension (76.9%), decreased neutrophil count (76.9%), and decreased white blood cell count (69.2%). Seven out of 12 evaluated patients achieved partial response, resulting in an overall response rate of 58.3% CONCLUSIONS: Copanlisib was well tolerated in Chinese patients with relapsed or refractory iNHL at the dose of 60 mg and demonstrated encouraging disease control, thus warranting further clinical investigation.

CLINICAL TRIAL REGISTRATION NUMBER

NCT03498430 (April 13, 2018).

Copanlisib in the Treatment of Relapsed Follicular Lymphoma: Utility and Experience from the Clinic

The phosphatidylinositol-3-kinase (PI3K) pathway is ubiquitous to multiple cellular processes and is intricately implicated in lymphomagenesis. The development of PI3K inhibitors has broadened treatment options for relapsed and/or refractory follicular lymphoma (FL) and currently three PI3K inhibitors have been approved in the third-line setting for FL, including idelalisib (oral), duvelisib (oral), and copanlisib (intravenous), with other agents under investigation. In this review, we discuss the clinical advance of copanlisib through preclinical to Phase III trials, its unique cellular targets and side effect profile that have poised it as a safer and equally efficacious option when compared to the older-generation oral PI3Kis, and its utility to the clinician as part of the therapeutic armamentarium for relapsed and/or refractory FL.

Copanlisib for the treatment of adults with relapsed follicular lymphoma

INTRODUCTION

Follicular lymphoma (FL) is the second most common histotype of lymphoma and is considered an incurable disease. The need for new treatment options has led to the development of innovative targeted agents, including inhibitors of the phosphatidylinositol-3-kinase (PI3K) pathway.

AREAS COVERED

Copanlisib, an intravenous pan-class I PI3K inhibitor, has been approved by the US Food and Drug Administration (FDA) for the treatment of relapsed FL in patients who have received at least two prior systemic therapies. In this article, we critically review the mechanism of action, clinical efficacy, safety, dosage, administration, and role of copanlisib in the treatment of relapsed FL.

EXPERT OPINION

Treatment with copanlisib results in clinically relevant and durable responses in heavily pretreated patients with relapsed or refractory FL. In addition, copanlisib has a manageable safety profile in this population, with low rates of severe hepatic transaminitis, diarrhea, colitis, and noninfectious pneumonitis. Further investigations of copanlisib within combination regimens will potentially allow to move copanlisib to an earlier line of therapy for FL. However, results of the CHRONOS-4 clinical trial evaluating copanlisib with standard chemoimmunotherapy (rituximab with bendamustine or CHOP) are not yet available.

Role of P-glycoprotein in the brain disposition of seletalisib: Evaluation of the potential for drug-drug interactions

Seletalisib is an orally bioavailable selective inhibitor of phosphoinositide 3-kinase delta (PI3Kδ) in clinical development for the treatment of immune-mediated inflammatory diseases. The present study investigated the role of P-gp in seletalisib disposition, especially brain distribution, and the associated risks of interactions. Seletalisib was found to be actively transported by rodent and human P-gp in vitro (transfected LLC-PK1 cells; K_m of ca. 20 µM), with minimal or no affinity for the other tested transporters. A distribution study in knockout rats (single oral dosing at 750 mg kg^-1) showed that P-gp restricts the brain disposition of seletalisib while having minimal effect on its intestinal absorption. Restricted brain penetration was also observed in cynomolgus monkeys (single oral dosing at 30 mg kg^-1) using brain microdialysis and cerebrospinal fluid sampling (K_p,uu of 0.09 and 0.24, respectively). These findings opened the question of potential pharmacokinetic interaction between seletalisib and P-gp inhibitors. In vitro, CsA inhibited the active transport of seletalisib with an IC₅₀ of 0.13 µM. In rats, co-administration of high doses of CsA (bolus iv followed by continuous infusion) increased the brain distribution of seletalisib (single oral dosing at 5 mg kg^-1). The observed data were found aligned with those predicted by in vitro-in vivo extrapolation. Based on the same extrapolation method combined with literature data, only very few P-gp inhibitors (i.e. CsA, quinine, quinidine) were predicted to increase the brain disposition of seletalisib in the clinical setting (maximal 3-fold changes).

Reactive intermediates in copanlisib metabolism identified by LC-MS/MS: phase I metabolic profiling

Copanlisib (CNB; Aliqopa™) is a novel, intravenous phosphoinositide 3-kinase inhibitor used to treat various solid and hematological malignancies. CNB was recently approved by the U.S. FDA to treat adults that relapsed after two preceding systemic therapies. Using LC-MS/MS, we screened for the in vitro metabolites of CNB formed in human liver microsomes (HLMs) and probed for the generation of reactive electrophiles using methoxyamine and potassium cyanide as nucleophiles to capture reactive electrophiles by forming stable adducts that are suitable for identification by LC-MS/MS. Seven CNB phase I metabolites generated by oxidation, hydroxylation, oxidative dealkylation, reduction, and N-oxidation were identified. In addition, four reactive electrophiles, 2 aldehydes and 2 iminium ions, were identified, and a prediction of the corresponding bioactivation mechanism is presented. The formation of reactive metabolites may be associated with the side effects reported for CNB. To our knowledge, this is the first report on the detailed structural characterization of reactive intermediates generated in CNB metabolism.

Copanlisib (CNB; Aliqopa™) is a novel, intravenous phosphoinositide 3-kinase inhibitor used to treat various solid and hematological malignancies.

Anti-liver cancer effect and the mechanism of arsenic sulfide in vitro and in vivo

PURPOSE

This study aimed at investigating the anti-tumor effect of arsenic sulfide (As₂S₂) against liver cancer both in vivo and in vitro and to elucidate its underlying mechanisms.

METHODS

Cell viability of the human hepatocellular carcinoma cell lines SMMC-7721, BEL-7402, HepG2 were measured by CCK-8 assay. The effects of As₂S₂ on cell proliferation and apoptosis of SMMC-7721 cells were investigated using Calcein-AM and PI staining, Hoechst 33258 staining, crystal violet staining, and JC-1 staining. Cell cycle and Annexin V/PI assay were analyzed via flow cytometry. The expression of apoptosis-related proteins, phosphorylation of PI3K and AKT were detected by Western blotting. H22-bearing mice model was established to evaluate the anti-tumor effect of As₂S₂ in vivo. HE staining, PCNA was observed via immunohistochemistry, and TUNEL assay was used to assess the anti-proliferation and pro-apoptotic effects of As₂S₂.

RESULTS

As₂S₂ significantly inhibited the growth of human hepatoma cells SMMC-7721, BEL-7402 and HepG2. As₂S₂ inhibited cell proliferation effectively by inducing G0/G1 cell cycle arrest in SMMC-7721 cells. As₂S₂ could increase Bax/Bcl-2 ratio, decrease mitochondrial membrane potential, promote the release of cytochrome c, increase the levels of cleaved caspase-3 and PARP, indicating that As₂S₂ induced apoptosis in SMMC-7721 cells via mitochondrial-mediated apoptosis pathway. Further research showed that As₂S₂ inhibited the PI3K/AKT signaling pathway leading to apoptotic cell death. In addition, As₂S₂ significantly inhibited tumor growth in H22-bearing mice and induced apoptosis by deactivating PI3K/AKT pathway, which was consistent with the in vitro results.

CONCLUSION

These findings suggested that As₂S₂ could induce apoptosis of liver cancer cells in vitro and in vivo, which was related to PI3K/AKT-mediated mitochondrial pathway and may provide a novel promising therapeutic agent for liver cancer treatment.

Spotlight on copanlisib and its potential in the treatment of relapsed/refractory follicular lymphoma: evidence to date

The importance of the phosphatidylinositol-3-kinase (PI3K) pathway in cell survival and proliferation has made it an attractive target in cancer therapy. The development of small molecule inhibitors for the PI3K pathway continues to provide treatment alternatives across a range of malignancy types. Several agents, including idelalisib, copanlisib and duvelisib, not only inhibit the PI3K pathway, but also have effects on associated mechanisms including the ATK and mTOR pathways. The advent of PI3K-specific small molecular inhibitors has led to increased efficacy with avoidance of an excessive toxicity profile. Key enzymes of the PI3K pathway exhibit differing expression in tissue types and roles in tumor pathogenesis. Copanlisib (BAY 80-6946) is a pan-specific PI3K small molecule inhibitor for four key isoforms with increased activity against PI3Kα and PI3Kδ, both important in B-cell malignancies. Follicular lymphoma is one of the most common indolent B-cell non-Hodgkin lymphomas worldwide. Follicular lymphoma like other indolent B-cell non-Hodgkin lymphomas is beleaguered by high relapse rates and the need for subsequent therapy options. Based on efficacy and a limited toxicity profile, copanlisib received accelerated US Food and Drug Administration approval for the treatment of adult patients with relapsed follicular lymphoma following two lines of therapy. Here, we review the development of copanlisib and the role of this agent in the treatment of follicular lymphoma.

Copanlisib: First Global Approval

Bayer are developing copanlisib (Aliqopa™)-a pan-class I phosphoinositide 3-kinase (PI3K) inhibitor-as a treatment for various haematological and solid malignancies. The US FDA has granted copanlisib accelerated approval for the treatment of adults with relapsed follicular lymphoma who have received at least two prior systemic therapies based on the results of a phase II trial. Phase III trials are underway evaluating copanlisib as treatment for relapsed/refractory diffuse large B-cell lymphoma and in combination with rituximab or rituximab-based chemotherapy or standard immunochemotherapy in patients with relapsed indolent B-cell non-Hodgkin's lymphoma. Phase I/II studies are underway in relapsed or refractory peripheral T-cell or NK/T-cell lymphoma, advanced cholangiocarcinoma, hormone receptor-positive HER2-negative stage I-IV breast cancer, HER2-positive breast cancer and recurrent and/or metastatic head and neck squamous cell carcinomas harbouring a PI3KCA mutation/amplification and/or a PTEN loss. This article summarizes the milestones in the development of copanlisib leading to this first approval for relapsed follicular lymphoma.