Phase I study of mitonafide with a 3-day administration schedule: early interruption due to severe central nervous system toxicity

Deep Eutectic Solvent (DES)-Mediated One-Pot Multicomponent Green Approach for Naphthalimide-Centered Acridine-1,8-dione Derivatives and Their Photophysical Properties

An efficient and green methodology to assemble various functionalized naphthalimide-centered acridine-1,8-dione derivatives involving a one-pot multicomponent protocol has successfully been developed. Herein, a variety of aromatic aldehydes, 1,3-diketones, 1,8-naphthanoic anhydride, and hydrazine hydrate have been condensed under a reusable, inexpensive, and biodegradable deep eutectic solvent (DES) of N,N'-dimethyl urea and l-(+)-tartaric acid to obtain the desired targets under operationally mild reaction conditions with outstanding conversions. Strikingly, in this strategy, the DES plays a dual role of a catalyst and solvent and was recycled efficiently in four consecutive runs with no substantial drop in the yield of the desired product. Interestingly, the easy recovery and high reusability of the DES make this simple yet efficient protocol environmentally desirable. Moreover, the preliminary photophysical properties of thus-prepared valuable molecules have also been investigated by ultraviolet-visible (UV-vis) and fluorescence spectroscopy.

Design, Synthesis, and Bioevaluation of a Novel Hybrid Molecular Pyrrolobenzodiazepine-Anthracenecarboxyimide as a Payload for Antibody-Drug Conjugate

A novel series of hybrid molecules combining pyrrolobenzodiazepine (PBD) and anthracenecarboxyimide pharmacophores were designed, synthesized, and tested for in vitro cytotoxicity against various cancer cell lines. The most potent compound from this series, 37b3, exhibited a subnanomolar level of cytotoxicity with an IC₅₀ of 0.17-0.94 nM. 37b3 induced DNA damage and led to tumor cell cycle arrest and apoptosis. We employed 37b3 as a payload to conjugate with trastuzumab to obtain the antibody-drug conjugate (ADC) T-PBA. T-PBA maintained its mode of target and internalization ability of trastuzumab. We demonstrated that T-PBA could be degraded through the lysosomal pathway to release the payload 37b3 after internalization. T-PBA showed a powerful killing effect on Her2-positive cancer cells in vitro. Furthermore, T-PBA significantly inhibited tumor growth in gastric and ovarian cancer xenograft mouse models without overt toxicity. Collectively, these studies suggest that T-PBA represents a promising new ADC that deserves further investigation.

Synthesis and in vitro anti-proliferative evaluation of naphthalimide–chalcone/pyrazoline conjugates as potential SERMs with computational validation

A series of naphthalimide-chalcone/pyrazoline conjugates was prepared and evaluated for their anti-breast cancer potential against estrogen responsive, i.e. MCF-7 (ER+), and triple-negative, i.e. MDA-MB-231 (ER−), cell lines. The structure-activity-relationship (SAR) was deduced based on the influence of linker length, substituents on the phenyl ring and the generated functionalities, on anti-proliferative activities. Docking simulations further delineate the type of interactions of the designed molecules with the selected targets. This report discloses the scope of triazole tethered naphthalimide-chalcone/pyrazoline conjugates as anti breast cancer agents.

Design, synthesis and anti-proliferative evaluation of naphthalimide–chalcone/pyrazoline conjugates.

Anticancer Activity and Topoisomerase II Inhibition of Naphthalimides with ω-Hydroxylalkylamine Side-Chains of Different Lengths

BACKGROUND

The substituted 1,8-Naphthalimides (1H-benzo[de]isoquinoline-1,3(2H)- diones) are known as DNA intercalators stabilizing DNA-Topoisomerase II complexes. This interaction disrupts the cleavage-relegation equilibrium of Topo II, resulting in formation of broken strands of DNA.

OBJECTIVE

To investigate the influence of type of substituents and substitution positions in 1,8- naphthalimde skeleton on the inhibition of Topoisomerase II activity.

METHODS

The starting 1,8-naphthalimide were prepared from acenaphthene by introduction of appropriate substituents followed by condensation with ω-hydroxylakylamines of different chain length. The substituents were introduced to 1,8-naphthalimide molecule by nucleophilic substitution of leaving groups like nitro or bromo present in 4 or 4,5- positions using the ω- hydroxylalkylamines. The bioactivity of obtained compounds was examined in model cell lines.

RESULTS

Antiproliferative activity of selected compounds against HCT 116 human colon cancer cells, human non-small cell lung cells A549 and non-tumorigenic BEAS-2B human bronchial epithelium cells was examined. Several of investigated compounds exhibit a significant activity (IC50 µM to 7 µM) against model cancer cell lines. It was demonstrated that upon treatment with concentration of 200 µM, all derivatives display Topo II inhibitory activity, which may be compared with activity of Amonafide.

CONCLUSION

The replacement of the nitro groups in the chromophore slightly reduces its anticancer activities, whereas the presence of both nitro group and ω-hydroxylalkylamine chain resulted in seriously increased anticancer activity. Obtained compounds showed Topo II inhibitory activity, moreover, influence of the substitution pattern on the ability to inhibit Topo II activity and cancer cells proliferation was observed.

Leishmanicidal Activity of Isoselenocyanate Derivatives

Conventional chemotherapy against leishmaniasis includes agents exhibiting considerable toxicity. In addition, reports of drug resistance are not uncommon. Thus, safe and effective therapies are urgently needed. Isoselenocyanate compounds have recently been identified with potential antitumor activity. It is well known that some antitumor agents demonstrate effects against Leishmania In this study, the in vitro leishmanicidal activities of several organo-selenium and organo-sulfur compounds were tested against Leishmania major and Leishmania amazonensis parasites, using promastigotes and intracellular amastigote forms. The cytotoxicity of these agents was measured in murine peritoneal macrophages and their selectivity indexes were calculated. One of the tested compounds, the isoselenocyanate derivative NISC-6, showed selectivity indexes 2- and 10-fold higher than those of the reference drug amphotericin B when evaluated in L. amazonensis and L. major, respectively. The American strain (L. amazonensis) was less sensitive to NISC-6 than L. major, showing a trend similar to that observed previously for amphotericin B. In addition, we also observed that NISC-6 significantly reduced the number of amastigotes per infected macrophage. On the other hand, we showed that NISC-6 decreases expression levels of Leishmania genes involved in the cell cycle, such as topoisomerase-2 (TOP-2), PCNA, and MCM4, therefore contributing to its leishmanicidal activity. The effect of this compound on cell cycle progression was confirmed by flow cytometry. We observed a significant increase of cells in the G₁ phase and a dramatic reduction of cells in the S phase compared to untreated cells. Altogether, our data suggest that the isoselenocyanate NISC-6 may be a promising candidate for new drug development against leishmaniasis.

Cancer cell-targeted two-photon fluorescence probe for the real-time ratiometric imaging of DNA damage

A sequential ICT fluorescence probe (ANF–Glu) was successfully utilized to spatially and temporally image DNA damage in cancer cells.

A first-in-human phase I, dose-escalation, multicentre study of HSP990 administered orally in adult patients with advanced solid malignancies

BACKGROUND

Heat-shock protein 990 (HSP990) is a potent and selective synthetic small-molecule HSP90 inhibitor. The primary objectives of this phase I first-in-human study were to determine dose-limiting toxicities (DLTs), maximum-tolerated dose (MTD) and recommended phase II dose (RP2D). Secondary objectives included characterisation of the safety profile, pharmacokinetics (PKs) and pharmacodynamics (PDs).

METHODS

Heat-shock protein 990 was administered orally once or two times weekly on a 28-day cycle schedule in patients with advanced solid tumours. Dose escalation was guided by a Bayesian logistic regression model with overdose control.

RESULTS

A total of 64 patients were enrolled. Fifty-three patients received HSP990 once weekly at 2.5, 5, 10, 20, 30, 50 or 60 mg, whereas 11 patients received HSP990 two times weekly at 25 mg. Median duration of exposure was 8 weeks (range 1-116 weeks) and 12 patients remained on treatment for >16 weeks. Dose-limiting toxicities occurred in seven patients and included diarrhoea, QTc prolongation, ALT/AST elevations and central neurological toxicities. The most common drug-related adverse events were diarrhoea, fatigue and decreased appetite. Further dose escalation beyond 60 mg once weekly was not possible owing to neurological toxicity. Rapid absorption, no drug accumulation and large interpatient variability in PK exposures were observed. No objective responses were seen; 25 patients had a best overall response of stable disease.

CONCLUSIONS

Heat-shock protein 990 is relatively well tolerated, with neurological toxicity being the most relevant DLT. The single agent MTD/RP2D of HSP990 was declared at 50 mg once weekly.

Study on the synthesis, biological activity and spectroscopy of naphthalimide-diamine conjugates

Eleven novel naphthalimide-diamine conjugates were synthesized and their structures were confirmed by elemental analysis, 1H-NMR, 13C-NMR and MS. Their in vitro antitumor activities were assessed using MTT assays on two cancerous cell lines K562, HCT116, and one normal hepatoma cell line QSG 7701. Compound 7f exhibited potent antitumor activity on HCT116 cells and favorable cell selectivity toward QSG 7701 compared with the positive control, amonafide. Moreover, 7f could block HeG2 cells in the G2/M phase and induce HeG2 cells apoptosis. The interaction of compound 7f with herring sperm DNA was studied by UV/vis absorption and fluorescence spectroscopy under physiological conditions (pH = 7.4). The observed spectral quenching of compound 7f by DNA and the displacement of EB from DNA-EB complex by compound 7f indicated that compound 7f could intercalate into DNA base pairs, which was also corroborated by the effect of KI on compound-DNA interaction. Further caloric fluorescent tests revealed that the quenching mechanism was a static type. Meanwhile, the binding constants, thermodynamic parameters and the effect of NaCl on compound-DNA interaction showed that the type of interaction force was mainly hydrogen bonds and the binding process was driven by hydrogen and van der Waals bonding.

Design, synthesis, and biological evaluation of substituted naphthalene imides and diimides as anticancer agent

Naphthalimmide (NI) and 1,4,5,8-naphthalentetracarboxylic diimide (NDI) derivatives were synthesized and evaluated for their antiproliferative activity. NDI derivatives 1-9 were more cytotoxic than the corresponding NI derivatives 10-18. The molecular mechanisms of 1 and 2 were investigated in comparison to mitonafide. They interacted with DNA, were not topoisomerase IIalpha poisons, triggered caspase activation, caused p53 protein accumulation, and down-regulated AKT survival. Furthermore, 1 and 2 caused a decrease of ERK1/2 and, unlike mitonafide, inhibited ERKs phosphorylation.

Phase I and pharmacokinetic study of LU79553, a DNA intercalating bisnaphthalimide, in patients with solid malignancies

PURPOSE

To determine the maximum-tolerated dose and characterize the pharmacokinetic behavior of LU79553, a novel bisnaphthalimide antineoplastic agent, when administered as a daily intravenous infusion for 5 days every 3 weeks.

PATIENTS AND METHODS

Patients with advanced solid malignancies received escalating doses of LU79553. Plasma sampling and urine collections were performed on both days 1 and 5 of the first course.

RESULTS

Thirty patients received 105 courses of LU79553 at doses ranging from 2 to 24 mg/m(2)/d. Proximal myopathy, erectile dysfunction, and myelosuppression precluded the administration of multiple courses at doses above 18 mg/m(2)/d. These toxicities were intolerable in two of six patients after receiving three courses at the 24-mg/m(2)/d dose level. At the 18-mg/m(2)/d dose, one of six patients developed febrile neutropenia and grade 2 proximal myopathy after three courses of LU79553. The results of electrophysiologic, histopathologic, and ultrastructural studies supported a drug-induced primary myopathic process. A patient with a platinum- and taxane-resistant papillary serous carcinoma of the peritoneum experienced a partial response lasting 22 months. Pharmacokinetics were dose-independent, optimally described by a three-compartment model, and there was modest drug accumulation over the 5 days of treatment.

CONCLUSION

Although no dose-limiting events were noted in the first two courses of LU79553, cumulative muscular toxicity precluded repetitive treatment with LU79553 at doses above 18 mg/m(2)/d, which is the recommended dose for subsequent disease-directed evaluations. The preliminary antitumor activity noted is encouraging, but the qualitative and cumulative nature of the principal toxicities, as well as the relatively small number of patients treated repetitively, mandate that rigorous and long-term toxicologic monitoring be performed in subsequent evaluations of this unique agent.

Structure-activity relationships for substituted bis(acridine-4-carboxamides): a new class of anticancer agents

A series of acridine-substituted bis(acridine-4-carboxamides) linked by a (CH2)3N(Me)(CH2)3 chain have been prepared by reaction of the isolated imidazolides of the substituted acridine-4-carboxylic acids with N,N-bis(3-aminopropyl)methylamine. These dimeric analogues of the mixed topoisomerase I/II inhibitor N-[2-(dimethylamino)ethyl]acridine-4-carboxamide (DACA), currently in clinical trial, show superior potencies to the corresponding monomeric DACA analogues in a panel of cell lines, including wild-type (JLC) and mutant (JLA and JLD) forms of human Jurkat leukemia. The latter mutant lines are resistant to topoisomerase II targeted agents because of lower levels of the enzyme. Analogues with small substituents (e.g., Me, Cl) at the acridine 5-position were clearly superior, with IC50's as low as 2 nM against the Lewis lung carcinoma and 11 nM against JLC. Larger substituents at any position caused a steady decrease in potency, likely due to lowering of DNA binding affinity. A small series of analogues of the most potent bis(5-methylDACA) compound, with second substituents (Me and Cl) in the 1- or 8- position had broadly similar potencies to the 5-Me compound, indicating that, while the 1- and 8-substituents are acceptable, they add little to the enhancing effect of the 5-methyl group. All of the compounds were at least equitoxic (some up to 4-fold more cytotoxic) against the mutant Jurkat lines than in the wild-type, consistent with a relatively greater effect on topoisomerase I compared with topoisomerase II. The bis(5-methylDACA) compound was found to inhibit the action of purified topoisomerase I in a cell-free assay. Compounds were on average 10-fold less cytotoxic in an MCF7 breast cancer line overexpressing P-glycoprotein than in the wild-type line and showed some selectivity for colon tumor lines in the NCI human tumor cell line panel. Several analogues produced significant growth delays in the relatively refractory subcutaneous colon 38 tumor model in vivo at substantially lower doses than DACA. The bis(acridine-4-carboxamides) represent a new and interesting class of potent topoisomerase inhibitors.

Phase I trial design: are new methodologies being put into practice?

BACKGROUND

The primary goal of phase I studies is to efficiently and accurately determine the recommended dose of a new agent for further investigation. Issues of concern ranging from the ethics of these trials to selection of starting dose and rapidity of dose escalation, have led to suggested modifications of the traditional phase I design. We wanted to assess the frequency with which these new approaches are being applied to recent phase I trials and, if possible, their impact.

METHODS

Reports of phase I trials of single agent cytotoxics published between 1993 and 1995 were identified by computer search and review of cancer journals. Data on starting dose, toxicology, dose escalation method, definition of dose limiting toxicity (DLT), actual maximum tolerated dose (MTD) and recommended phase II dose were abstracted.

RESULTS

Reports of 46 phase I trials were identified: 27 were the first clinical studies of 17 new cytotoxic agents (group A) and 19 were repeat studies of 14 agents (group B). Starting doses in group A were based on preclinical animal toxicology (usually mouse or dog) and for group B on previous clinical experience. Dog toxicology appropriately influenced starting dose in 3 of 6 trials. The majority of group A (19/27) studies employed modified Fibonacci dose escalation; group B studies commonly escalated doses by fixed increments. The definition of DLT was highly variable across studies. MTD was usually defined as the dose level at which > 2/6 patients experienced DLT but several studies required 3-4/6 patients. In 30 trials, the recommended phase II dose was one dose level below the MTD; but in 10 trials the terms MTD and recommended phase II dose were considered synonymous.

CONCLUSION

Despite proposed new methodologies (particularly dose escalation) for phase I trials, very few are being employed in practice. A concerted effort should be made to prospectively evaluate these to determine which provides the best combination of safety and efficacy. In addition, the lack of standardization in the definition of limiting toxicity is surprising. Those involved in drug development should strive for agreement on the acceptable degree of toxicity for phase II dose selection.

Phase II study of mitonafide in non-small cell lung cancer (NSCLC)

BACKGROUND

The new intercalative agent Mitonafide was shown in early clinical trials to be toxic to the central nervous system when administered as a short intravenous infusion, but not when given as a 120-hour continuous infusion. Thus, clinical development in different tumor types was pursued using only this administration schedule.

PATIENTS AND METHODS

Forty-nine patients with previously untreated non-small cell lung cancer (NSCLC) and at least one measurable site received Mitonafide as a 120-hour continuous (5 days) infusion every 3 weeks. The starting dose was 170 mg/m2/day x 5 in the first 26 patients and 200 mg/m2/day x 5 in the remainder. Patients were evaluated for toxicity after each course and for response every two courses and remained on treatment until excessive toxicity or disease progression were observed. A special test, the "Mini-mental state", was used to assess patients' cognitive functions.

RESULTS

Of the 49 patients entered, 42 were evaluable for response and toxicity. Toxicity consisted mainly of myelosuppression and no neurologic side effects were observed. Only one patient presented a partial response.

CONCLUSIONS

Although definitively safe with this schedule of administration, Mitonafide is not active in NSCLC.