Indazole Carboxylic Acid Research Articles

A phase II clinical and pharmacokinetic study of Lonidamine in patients with advanced breast cancer

Lonidamine is a substituted indazole carboxylic acid with a unique mechanism of action and early clinical studies have reported anti-tumour activity. In a phase II study 32 patients with previously treated advanced breast cancer were given Lonidamine in a daily divided oral dose of 600 mg. Of 28 patients evaluable for response, three (11%) achieved a partial response (4-24+ months) and three (11%) a minor response. Two patients have stable disease (greater than 3 months) and 20 progressed. Toxicity was very mild. Sixteen (53%) of 31 patients had myalgia which lasted a median of 2 weeks. This was investigated with nuclear magnetic resonance spectroscopy in four patients but the changes were unrelated to the degree of myalgia. No other major side-effect was seen, and no dose reduction was required. Lonidamine pharmacokinetics have been investigated in 17 patients 1 month after the start of therapy. Lonidamine was detected in the plasma of all patients, but there was no clear relationship between Lonidamine levels and clinical response or toxicity. Lonidamine appears to be active against advanced breast cancer and its low toxicity would allow combination studies with chemotherapy.

Lonidamine in Non-Small-Cell Lung Cancer: A Phase II Study

The activity of lonidamine (a derivative of indazole-carboxylic acid and a new drug with a characteristic antitumor activity) was evaluated in non-small-cell lung cancer (NSCLC). Twenty-five patients with NSCLC with or without prior treatment received lonidamine at the dose of 450 mg/daily p.o. up to progression. Objective responses obtained were: 3 (12%) partial responses and 3 (12%) minor responses with a mean duration of 13.7 weeks for partial responses. Mean duration of treatment was 20 weeks (range 4-97+). During to the drug's characteristics, bone marrow toxicity was not observed; myalgia and mild testicular pain were the most significant side effects.

Lonidamine: a non-mutagenic antitumor agent

Lonidiamine is a novel indazole-carboxylic acid with antitumour properties; it has been studied for potential mutagenicity in a comprehensive battery of tests. In assays for the induction of gene mutations in prokaryotes (Ames test) and eukaryotes (induction of HPRT mutations in CHO cells), negative results were obtained. There was no evidence of the induction of chromosomal damage in cultured mammalian cells in vitro. No mutagenic activity was observed in tests for chromosomal damage in vivo, in somatic cells (micronucleus test) or in germinal cells (dominant lethal test). These negative results are consistent with observations indicating that lonidamine affects cellular energy processes, rather than the mechanisms of cell division. The lack of mutagenic properties suggests that lonidamine may present significant advantages in treatment of some tumours, offering a reduced risk of resistant clones, secondary cancer and heritable genetic damage.

The differential effects of the indazole-carboxylic acid derivative, tolnidamine, on Sertoli cell protein secretion.

The indazole-carboxylic acid derivative tolnidamine (TOL) has marked antispermatogenic activity in rats. Previous morphological and biochemical studies indicate that Sertoli cells are one of the targets of this compound. The aim of this study was to assess the effect of TOL on the in vitro secretory functions of primary Sertoli cell-enriched cultures prepared from rats of different ages by monitoring the changes of three known Sertoli cell proteins, androgen binding protein (rABP), transferrin (rTF), and testibumin (rTB). The addition of TOL at the beginning of the culture period reduced the plating efficiency of Sertoli cells; however, TOL did not induce a significant change in cell number if it was added 24 h after plating of the cells. Sertoli cell-enriched cultures prepared from tests of 10-day-old rats were highly sensitive to TOL as evidenced by a marked inhibition in secretions of rABP, rTB, and rTF in all experiments. In cultures prepared from 15- and 20-day-old rats, TOL had no apparent effect on rABP secretion, but reduced rTF and increased rTB secretion. Thus, TOL has a differential effect on the secretion of individual proteins in Sertoli cells cultured from rats between 10 and 20 days of age. This phenomenon is presumably a consequence of the progressive maturation of Sertoli cells in the seminiferous epithelium.

The combined use of radiation therapy and lonidamine in the treatment of brain metastases

Lonidamine is an indazole carboxylic acid that has been shown to be synergistic with radiotherapy (RT) in tissue culture and animal models. Clinical experience has shown that lonidamine is well-tolerated, and appears to potentiate the activity of conventional chemotherapy in the treatment of brain metastases. A prospective randomized trial was undertaken to evaluate the use of lonidamine in combination with RT in the treatment of brain metastases. All patients received 3000 cGy of whole brain radiotherapy (WBRT). Fifty eight patients were enrolled; 31 received lonidamine plus WBRT and 27 received WBRT alone. There was no significant difference in response rate or survival between the treatment groups. Lonidamine blood levels were measured in 30 of the 31 patients who received the drug, and were therapeutic (greater than or equal to 15 micrograms/ml) in 50%. Survival and response rate were unaffected by the presence or absence of a therapeutic lonidamine level. The most common side-effects of lonidamine were myalgia, testicular pain, anorexia, and ototoxicity; however, only 2 patients had to discontinue the drug because of intolerable myalgias. No serious organ toxicity or myelosuppression was observed.

The effects of the indazole carboxylic acid derivative, tolnidamine, on testicular function: I. Early changes in androgen binding protein secretion in the rat.

The indazole carboxylic acid derivative, tolnidamine, has marked antispermatogenic activity in several animal species. In this study, we assessed the effect of tolnidamine on rat Sertoli cell function both in vivo and in vitro, using androgen binding protein (rABP) as a marker. Groups of six male rats were killed 2, 4, 8, 16, 32, 64 hours and 5, 8, and 12 days following tolnidamine administration (250 mg/kg by oral gavage). There was a progressive reduction in both testicular and epididymal weights. Serum FSH levels did not change and LH showed a transient increase between 64 hours and 8 days. Except for an initial increase at 2 hours, there were no changes in serum testosterone. Epididymal rABP concentration and content declined as early as 8 hours, with the lowest values occurring at 5 and 12 days. By 16 hours, there was an increase in testicular rABP, which was also evident at 8 days and 12 days. Within 16 hours after tolnidamine, there was a rise in serum rABP, which persisted until the end of the experiment. When another indazole carboxylic acid derivative, lonidamine, was administered (250 mg/kg), similar changes were evident in epididymal and serum rABP at 32 hours, but the rapid decrease in testicular rABP suggested a different mechanism of action. In another experiment, single oral doses of tolnidamine (50, 100, 250, and 500 mg/kg) were administered to other groups of rats and the animals were killed after 24 hours and 5 days. With increasing doses of tolnidamine, there was a reduction in epididymal rABP concomitant with an increase in testis and serum rABP levels.(ABSTRACT TRUNCATED AT 250 WORDS)

Phase I toxicologic study of Lonidamine in cancer patients.

15 patients with metastatic cancer were treated with Lonidamine, a substituted indazole carboxylic acid active against the Lewis lung and Sarcoma 180 tumors. Single doses of 600 mg (350-400 mg/m2) mostly induced somnolence and gastro-intestinal side effects. Toxicity occurring during chronic administration of Lonidamine at doses ranging between 45 and 275 mg/m2 twice daily, mainly consisted of somnolence, myalgias, hyperesthesia and mild hair loss. Myalgias and hyperesthesias were markedly relieved with prednisone 5 mg twice daily. No laboratory abnormalities were seen. In 1 patient with breast cancer resistant to standard chemotherapeutic agents, a 30% reduction of measurable tumor masses was seen. In view of the lack of overlapping toxicity between Lonidamine and other chemotherapeutic drugs, and of its potential activity, it is suggested that phase II studies of Lonidamine be initiated at a dose of 135 mg/m2 twice daily.

Phase II evaluation of Lonidamine in patients with advanced malignancy.

Lonidamine, a substituted indazole carboxylic acid with unique effects on cellular respiration, was studied in 27 patients with advanced malignancies. Of the 18 evaluable patients, 5 had small-cell lung cancer, 3 had non-small-cell lung cancer, 3 sarcoma, 2 breast cancer, and 5 other tumour types. All but 1 had had extensive prior treatment. A partial response was seen in 1 patient with metastatic synovial sarcoma, and tumour growth inhibition was demonstrated in 2 other cases. The major toxicity encountered was myalgia (66.6%) which was incompletely ameliorated by prednisone and required dose reduction in 2 patients and cessation of drug in 3. Other toxicities included auditory changes, anorexia, nausea and vomiting, diarrhoea, skin sensitivity, and conjunctivitis. No added toxicity was seen, when Lonidamine was combined with other chemotherapeutic agents. No correlation between Lonidamine dose and serum lactate levels was seen, although 4 patients showed a progressive increase in lactate levels over time, thought to be related to their increasing tumour burden. 5 patients demonstrated a dramatic fall in serum testosterone levels 4-8 weeks after starting Lonidamine which was accompanied by an increase in luteinizing hormone levels in 3 patients. In summary, modest antitumour activity was demonstrated in 3 patients; moderate toxicity was seen in most patients, but was usually tolerable. Further studies of Lonidamine are warranted in less heavily treated patients, alone or in combination with other chemotherapeutic agents.

Phase II study of Lonidamine in cancer patients.

12 patients with metastatic cancer were treated with the substituted indazole carboxylic acid Lonidamine at oral daily doses of 270 mg/m2. Toxicity, consisting mainly of myalgias, somnolence, hyperesthesia, anorexia and vomiting, generally decreased or disappeared over time despite continuing drug administration at unmodified dosage. Myalgias and hyperesthesias were markedly relieved with prednisone 5 mg twice daily. No laboratory abnormalities were seen. Partial responses were observed in a patient with hypernephroma and in a patient with breast cancer. Disease-oriented phase II studies with this new anticancer agent are warranted.

Basic and Applied Research in the Study of Indazole Carboxylic Acids

Basic and Applied Research in the Study of Indazole Carboxylic Acids

Perspectives for the use of indazolecarboxylic acids as male antifertility agents.

Perspectives for the use of indazolecarboxylic acids as male antifertility agents.