Characterization of Ethyl Butyrate-Induced Cough Before and After Breath Control Techniques in Healthy Adults

PURPOSE

Methods for cough elicitation frequently involve aerosolized tussive agents. Here, we sought to determine whether healthy individuals demonstrate a quantifiable cough response after inhaling a volatile ester and if breath control techniques modify this chemically induced cough response.

METHOD

Sixty adult male and female participants inhaled prepared liquid dilutions of ethyl butyrate dissolved in paraffin oil at 20%, 40%, and 60% v/v concentrations in triplicate, with presentation order randomized. We delivered stimuli through a face mask connected to an olfactometer and respiratory pneumotachograph. Participants rated sensations of their urge to cough and pleasantness of the odor while cough airflow was measured. Following baseline testing, participants were randomized to implement pursed-lip breathing or slow-paced breathing after inhaling ethyl butyrate to determine the effects of breath control on cough measures.

RESULTS

Inhaled ethyl butyrate elicited cough in 70% of participants. Higher concentrations of ethyl butyrate resulted in significantly greater sensation of the urge to cough, F(2, 80) = 10.72, p < .001, and significantly more generated coughs, F(2, 63) = 13.14, p < .001. Compared to baseline, participants rated significantly decreased urge to cough during breath control techniques, F(1, 40) = 11.01, p = .0019. No significant changes were observed in the number of generated coughs between baseline and breath control techniques, F(1, 31) = 7.23, p = .01.

CONCLUSIONS

Airborne ethyl butyrate is a tussigenic agent in humans. Our findings provide opportunities for future research directions in normal and disordered cough responses to volatile compounds.

Selective Peroxisome Proliferator-Activated Receptor Alpha Modulators (SPPARMα): New Opportunities to Reduce Residual Cardiovascular Risk in Chronic Kidney Disease?

PURPOSE OF REVIEW

Chronic kidney disease (CKD) poses a major global challenge, which is exacerbated by aging populations and the pandemic of type 2 diabetes mellitus. Much of the escalating burden of CKD is due to cardiovascular complications. Current treatment guidelines for dyslipidemia in CKD prioritize low-density lipoprotein cholesterol management, but still leave a high residual cardiovascular risk. Targeting elevated triglycerides and low plasma high-density lipoprotein cholesterol, a common feature of CKD, could offer additional benefit. There are, however, safety issues with current fibrates (peroxisome proliferator-activated receptor alpha [PPARα] agonists), notably the propensity for elevation in serum creatinine, indicating the need for new approaches.

RECENT FINDINGS

Interactions between the ligand and PPARα receptor influence the specificity and potency of receptor binding, and downstream gene and physiological effects. The peroxisome proliferator-activated receptor alpha modulator (SPPARMα) concept aims to modulate the ligand structure so as to enhance binding at the PPARα receptor, thereby improving the ligand's selectivity, potency, and safety profile. This concept has led to the development of pemafibrate, a novel SPPARMα agent. This review discusses evidence that differentiates pemafibrate from current fibrates, especially the lack of evidence for elevation in serum creatinine or worsening of renal function in high-risk patients, including those with CKD. Differentiation of pemafibrate from current fibrates aims to address unmet clinical needs in CKD. The ongoing PROMINENT study will provide critical information regarding the long-term efficacy and safety of pemafibrate in patients with type 2 diabetes mellitus, including those with CKD, and whether the favorable lipid-modifying profile translates to reduction in residual cardiovascular risk.

Pemafibrate, a New Selective PPARα Modulator: Drug Concept and Its Clinical Applications for Dyslipidemia and Metabolic Diseases

PURPOSE OF REVIEW

Reduction of serum low-density lipoprotein cholesterol (LDL-C) levels by statins, ezetimibe and proprotein convertase subtilisin/kexin type 9 (PCSK9) inhibitors has been shown to significantly reduce cardiovascular events risk. However, fasting and postprandial hypertriglyceridemia as well as reduced high-density lipoprotein cholesterol (HDL-C) remain as residual risk factors of atherosclerotic cardiovascular diseases (ASCVD). To treat patients with hypertriglyceridemia and/or low HDL-C, drugs such as fibrates, nicotinic acids, and n-3 polyunsaturated fatty acids have been used. However, fibrates were demonstrated to cause side effects such as liver dysfunction and increase in creatinine levels, and thus large-scale clinical trials of fibrates have shown negative results for prevention of ASCVD. The failure could be attributed to their low selectivity and potency for binding to peroxisome proliferator-activated receptor (PPAR) α. To resolve these issues, the concept of selective PPARα modulator (SPPARMα) with a superior balance of efficacy and safety has been proposed and pemafibrate (K-877) has been developed.

RECENT FINDINGS

Pemafibrate, one of SPPARMsα, was synthesized by Kowa Company, Ltd. for better efficiency and safety. Clinical trials in Japan have established the superiority of pemafibrate on effects on serum triglycerides (TG) reduction and HDL-C elevation as well safety. Although available fibrates showed worsening of liver and kidney function test values, pemafibrate indicated improved liver function test values and was less likely to increase serum creatinine or decrease estimated glomerular filtration rate (eGFR). Very few drug-drug interactions were observed even when used concomitantly with statins. Furthermore, pemafibrate is metabolized in the liver and excreted into the bile, while many of available fibrates are mainly excreted from the kidney. Therefore, pemafibrate can be used safely even in patients with impaired renal function since there is no significant increase in its blood concentration. A large-scale trial of pemafibrate, PROMINENT, for dyslipidemic patients with type 2 diabetes is ongoing. Pemafibrate is one of novel SPPARMsα and has superior benefit-risk balance compared to conventional fibrates and can be applicable for patients for whom the usage of existing fibrates is difficult such as those who are taking statins or patients with renal dysfunction. In the current review, all the recent data on pemafibrate will be summarized.

SPPARM alpha: the Lazarus effect

PURPOSE OF REVIEW

Atherogenic dyslipidaemia, characterized by high plasma triglycerides (a surrogate for triglyceride-rich remnant lipoproteins) and low high-density lipoprotein cholesterol (HDL-C), is prevalent in patients with type 2 diabetes mellitus (T2DM) and contributes to a high modifiable residual cardiovascular risk. Fibrates are effective in managing hypertriglyceridaemia but lack consistent cardiovascular benefit in clinical trials and exhibit pharmacokinetic interaction with statins (gemfibrozil) and renal and hepatic safety issues (fenofibrate). The selective peroxisome proliferator-activated receptor alpha modulator (SPPARMα) paradigm offers potential for improving potency, selectivity and the benefit-risk profile.

RECENT FINDINGS

The present review discusses evidence for the novel SPPARMα agonist, pemafibrate. Clinical trials showed robust lowering of triglyceride-rich lipoproteins, elevation in HDL-C and nonlipid beneficial effects including anti-inflammatory activity. There was a favourable safety profile, with no increase in serum creatinine, evident with fenofibrate, and improved renal and hepatic safety. The cardiovascular outcomes study PROMINENT is critical to confirming the SPPARMα concept by validating reduction in residual cardiovascular risk in patients with T2DM and long-term safety.

SUMMARY

SPPARMα offers a new paradigm for reducing residual cardiovascular risk in T2DM. PROMINENT will be critical to differentiating the first SPPARMα, pemafibrate, as a novel therapeutic class distinct from current fibrates.

Efficacy and safety of pemafibrate in people with type 2 diabetes and elevated triglyceride levels: 52-week data from the PROVIDE study

The aim of this study was to evaluate the efficacy and safety of pemafibrate in people with type 2 diabetes and hypertriglyceridaemia over a 52-week period. Participants were randomly assigned to receive treatment with placebo or pemafibrate at a dose of 0.2 or 0.4 mg/d for 24 weeks (treatment period 1). The main results from treatment period 1 have been reported previously. The assigned treatment was continued up to week 52, except that the placebo was changed to pemafibrate 0.2 mg/d after week 24 (treatment period 2). The percentage changes in fasting serum triglyceride (TG) levels at week 52 (last observation carried forward) were -48.2%, -42.3%, and -46.4% in the placebo/pemafibrate 0.2 mg/d (n = 57), pemafibrate 0.2 mg/d (n = 54), and pemafibrate 0.4 mg/d (n = 55) groups, respectively. Levels of TG, non-HDL cholesterol and total cholesterol stably decreased, whereas levels of HDL cholesterol increased with pemafibrate treatments over 52 weeks. Pemafibrate was well tolerated throughout the study period. The present study is the first to show that pemafibrate treatment substantially ameliorated lipid abnormalities and was well tolerated for 52 weeks in people with type 2 diabetes and hypertriglyceridaemia.

The selective peroxisome proliferator-activated receptor alpha modulator (SPPARMα) paradigm: conceptual framework and therapeutic potential : A consensus statement from the International Atherosclerosis Society (IAS) and the Residual Risk Reduction Initiative (R3i) Foundation

In the era of precision medicine, treatments that target specific modifiable characteristics of high-risk patients have the potential to lower further the residual risk of atherosclerotic cardiovascular events. Correction of atherogenic dyslipidemia, however, remains a major unmet clinical need. Elevated plasma triglycerides, with or without low levels of high-density lipoprotein cholesterol (HDL-C), offer a key modifiable component of this common dyslipidemia, especially in insulin resistant conditions such as type 2 diabetes mellitus. The development of selective peroxisome proliferator-activated receptor alpha modulators (SPPARMα) offers an approach to address this treatment gap. This Joint Consensus Panel appraised evidence for the first SPPARMα agonist and concluded that this agent represents a novel therapeutic class, distinct from fibrates, based on pharmacological activity, and, importantly, a safe hepatic and renal profile. The ongoing PROMINENT cardiovascular outcomes trial is testing in 10,000 patients with type 2 diabetes mellitus, elevated triglycerides, and low levels of HDL-C whether treatment with this SPPARMα agonist safely reduces residual cardiovascular risk.

Long-Term Efficacy and Safety of Pemafibrate, a Novel Selective Peroxisome Proliferator-Activated Receptor-α Modulator (SPPARMα), in Dyslipidemic Patients with Renal Impairment

Pemafibrate (K-877) is a novel selective peroxisome proliferator-activated receptor-α modulator (SPPARMα) with a favorable benefit-risk balance. Previous clinical trials of pemafibrate used stringent exclusion criteria related to renal functions. Therefore, we investigated its safety and efficacy in a broader range of patients, including those with chronic kidney disease (CKD). In this multicenter, single-arm, open-label, phase III trial, 0.2⁻0.4 mg/day pemafibrate was administered for 52 weeks to 189 patients with hypertriglyceridemia and an estimated glomerular filtration rate (eGFR) ≥ 45 mL/min/1.73 m² on statin or regardless of eGFR when statin was not administered. Post-hoc analyses were performed on subgroups stratified by baseline eGFR. Triglyceride levels decreased by 45.9% at week 52 (last-observation-carried-forward). These reductions were not correlated with baseline eGFR. The eGFR < 30 mL/min/1.73 m² subgroup showed the greatest reduction in chylomicron, very low-density lipoprotein, small low-density lipoprotein cholesterol levels, and an increase in high-density lipoprotein cholesterol levels. The incidences of adverse events and adverse drug reactions were 82.0% and 31.7%, respectively, and these were not associated with baseline eGFR. In CKD patients, pemafibrate blood concentrations were not elevated. Pemafibrate showed a good safety profile and efficacy in correcting lipid abnormalities in a broad range of patients, including those with CKD.

The safety, tolerability, and pharmacokinetic profile of GSK2838232, a novel 2nd generation HIV maturation inhibitor, as assessed in healthy subjects

This work aimed to assess the safety, tolerability, pharmacokinetics (PK), and relative bioavailability of GSK2838232, an investigational HIV maturation inhibitor. GSK2838232 was administered over four dose-escalation studies in healthy subjects which assessed single oral doses (5-250 mg) and repeat doses (up to 200 mg once or twice daily) ±100 mg ritonavir (RTV) once daily. GSK2838232 administration (up to 250 mg) to 124 subjects across four studies resulted in few mild adverse events (AEs) with similar frequencies to placebo. There were no clearly identified drug-related AEs. GSK2838232 tested fasted was quickly absorbed with a tmax of 2-3 hours. With food, the absorption was delayed and more variable, with ~60% increase in AUC and Cmax. Overall, following single doses GSK2838232 AUC and Cmax generally exhibited proportional PK from 50 to 100 mg dose without RTV and from 50 to 250 mg with RTV and following repeated doses of 20-200 mg with RTV. In relative bioavailability studies, a micronized formulation was found to be suitable for development. At steady state, RTV increased GSK2838232 AUC and Cmax by 10- and 3-fold, respectively. Half-life was prolonged from ~17 hours nonboosted to ~34 hours with RTV. This boosting effect was also seen in repeat-dose GSK2838232 studies, which achieved the targeted plasma exposure with GSK2838232 as a once-daily regimen of up to 200 mg with RTV. The results of these studies demonstrated a favorable safety and PK profile for GSK2838232 and support its investigation for the treatment of HIV infection.

A dose-escalation phase IIa study of 2,2-dimethylbutyrate (HQK-1001), an oral fetal globin inducer, in sickle cell disease

2,2-Dimethylbutyrate (HQK-1001), an orally-bioavailable promoter-targeted fetal globin gene-inducing agent, was evaluated in an open-label, randomized dose-escalation study in 52 subjects with hemoglobin SS or S/β(0) thalassemia. HQK-1001 was administered daily for 26 weeks at 30 mg/kg (n = 15), 40 mg/kg (n = 18) and 50 mg/kg (n = 19), either alone (n = 21) or with hydroxyurea (n = 31). The most common drug-related adverse events were usually mild or moderate and reversible. Gastritis was graded as severe in three subjects at 40 mg/kg and was considered the dose-limiting toxicity. Subsequently all subjects were switched to the maximum tolerated dose of 30 mg/kg. Due to early discontinuations for blood transfusions, adverse events or non-compliance, only 25 subjects (48%) completed the study. Drug plasma concentrations were sustained above targeted levels at 30 mg/kg. Increases in fetal hemoglobin (Hb F) were observed in 42 subjects (80%), and 12 (23%) had increases ≥4%. The mean increase in Hb F was 2% [95% confidence interval (CI), 0.8-3.2%] in 21 subjects receiving HQK-1001 alone and 2.7% (95% CI, 1.7-3.8%) in 31 subjects receiving HQK-1001 plus hydroxyurea. Total hemoglobin increased by a mean of 0.65 g/dL (95% CI, 0.5-1.0 g/dL), and 13 subjects (25%) had increases ≥1 g/dL. Future studies are warranted to evaluate the therapeutic potential of HQK-1001 in sickle cell disease. .

A phase 1/2 trial of HQK-1001, an oral fetal globin inducer, in sickle cell disease

Therapeutics which reduce the pathology in sickle cell syndromes are needed, particularly noncytotoxic therapeutics. Fetal hemoglobin (HbF, α(2) γ(2) ) is established as a major regulator of disease severity; increased HbF levels correlate with milder clinical courses and improved survival. Accordingly, sodium dimethylbutyrate (HQK-1001), an orally-bioavailable, promoter-targeted fetal globin gene-inducing agent, was evaluated in a randomized, blinded, dose-ranging Phase I/II trial in 24 adult patients with HbSS or S/β thalassemia, to determine safety and tolerability of three escalating dose levels. The study therapeutic was administered once daily for two 6-week cycles, with a two-week interim dose holiday. Twenty-one patients completed the study. Five patients received study drug at 10 or 20 mg/kg doses, seven patients received study drug at 30 mg/kg/dose, and 4 patients received placebo. HQK-1001 was well-tolerated with no unexpected drug-related adverse events; a dose-limiting toxicity was not identified. Plasma drug levels were sustained above targeted levels for 24 hr. Increases in HbF above baseline were observed particularly with 30 mg/kg/day doses; in five of seven treated patients, a mean absolute increase in HbF of 0.2 g/dl and a mean increase in total hemoglobin (Hgb) of 0.83 g/dl above baseline were observed, whereas no increases occurred in placebo-treated controls. These findings of favorable PK profiles, tolerability, early rises in HbF, and total Hgb indicate that trials of longer duration appear warranted to more definitively evaluate the therapeutic potential of HQK-1001 in sickle cell disease.

One-year treatment with 0.1% tacrolimus ointment versus a corticosteroid regimen in adults with moderate to severe atopic dermatitis: A randomized, double-blind, comparative trial

A one-year, randomized, double-blind study was conducted in 80 patients with atopic dermatitis treated with tacrolimus ointment or a corticosteroid regimen (hydrocortisone acetate 1% ointment for head and neck, hydrocortisone butyrate 0.1% ointment for trunk and limbs) to compare efficacy and safety, and effects on Th2-reactivity. The study was completed by 36/40 patients in the tacrolimus group, and 31/40 patients in the corticosteroid group. In both groups affected body surface area, eczema area and severity index, and transepidermal water loss decreased at months 6 and 12. Tacrolimus was superior for all efficacy scores at month 6, and in the head and neck area at month 12. Recall antigen reactivity increased at month 12 in both groups. Adverse events were reported by 40/40 patients in the tacrolimus, and by 34/40 patients in the corticosteroid group. Long-term treatment with topical tacrolimus or a corticosteroid regimen improves atopic dermatitis and recall antigen reactivity, suggesting an improvement in the Th1/Th2-balance.

MN 001: KCA 757, KCA-757, MN-001

MN 001 is an orally bioavailable anti-inflammatory agent, originated by Kyorin Pharmaceutical, which is being developed in clinical trials by the US company MediciNova for the treatment of interstitial cystitis and asthma. Kyorin is developing the drug as KCA 757 for these indications. The actions of the drug are described by MediciNova as consisting of eosinophil migration inhibition, leukotriene antagonism, and phosphodiesterase IV inhibition. Other mechanisms described for MN 001 include the inhibition of phosphodiesterases III, 5-lipoxy-genase, phospholipase C as well as thromboxane A2. Development of an immediate-release formulation of MN 001 has been discontinued. An extended-release formulation remains in development. MediciNova is looking for partnering/outlicensing opportunities for MN 001 in North America and Europe. MediciNova licensed MN 001 from Kyorin Pharmaceutical in March 2002, and now holds exclusive worldwide rights, excluding Japan, China, Taiwan and South Korea, to develop and commercialise the drug. The phase III clinical programme of immediate-release MN 001 was initiated by Medicinova in the US in November 2006. In the first phase III trial, 705 patients with mild to moderate asthma were to be randomised to receive MN 001 (750 mg twice daily, 500 mg three times daily) or placebo for 12 weeks. The change from baseline in mean forced expiratory volume in 1 second (FEV(1)) will be the primary endpoint. The primary endpoint was met in a phase II study of MN 001 in patients with mild to moderate asthma. The trial evaluated the efficacy of three different doses of MN 001 for the treatment of asthma. Results have been reported. MediciNova has received Notices of Allowance from the US Patent and Trademark Office for three patent applications covering certain compositions, uses and manufacturing processes associated with MN 001. MN 001 has received patent protection through at least 2023.

A phase 1/2 trial of arginine butyrate and ganciclovir in patients with Epstein-Barr virus-associated lymphoid malignancies

Malignancies associated with latent Epstein-Barr virus (EBV) are resistant to nucleoside-type antiviral agents because the viral enzyme target of these antiviral drugs, thymidine kinase (TK), is not expressed. Short-chain fatty acids, such as butyrate, induce EBV-TK expression in latently infected B cells. As butyrate has been shown to sensitize EBV(+) lymphoma cells in vitro to apoptosis induced by ganciclovir, arginine butyrate in combination with ganciclovir was administered in 15 patients with refractory EBV(+) lymphoid malignancies to evaluate the drug combination for toxicity, pharmacokinetics, and clinical responses. Ganciclovir was administered twice daily at standard doses, and arginine butyrate was administered by continuous infusion in an intrapatient dose escalation, from 500 mg/(kg/day) escalating to 2000 mg/(kg/day), as tolerated, for a 21-day cycle. The MTD for arginine butyrate in combination with ganciclovir was established as 1000 mg/(kg/day). Ten of 15 patients showed significant antitumor responses, with 4 CRs and 6 PRs within one treatment cycle. Complications from rapid tumor lysis occurred in 3 patients. Reversible somnolence or stupor occurred in 3 patients at arginine butyrate doses of greater than 1000 mg/(kg/day). The combination of arginine butyrate and ganciclovir was reasonably well-tolerated and appears to have significant biologic activity in vivo in EBV(+) lymphoid malignancies which are refractory to other regimens.

Fas ligand-mediated lethal hepatitis after rapid lysis of a localized natural killer cell lymphoma

Natural killer (NK) cell malignancies have been associated with neutropenia and disturbances of liver function tests, thought to be related to high levels of soluble Fas ligand (FasL) in the circulation. We report a case of fulminant hepatitis occurring 3 weeks after the initiation of salvage therapy by arginine butyrate and ganciclovir for refractory Epstein-Barr virus-positive NK cell lymphoma. Pathologic examination revealed disappearance of the NK tumor and massive liver injury caused by apoptosis of virtually all hepatocytes. Immunohistochemistry revealed an intense staining for FasL. To our knowledge, this is the first description of the occurrence of FasL-mediated lethal hepatitis after lysis of a NK cell lymphoma.

Oral butyrate for mildly to moderately active Crohn's disease

BACKGROUND

Butyrate exerts anti-inflammatory effects in experimental colitis and on Crohn's disease lamina propria mononuclear cells in vitro.

AIM

To explore the efficacy and safety of oral butyrate in Crohn's disease.

METHODS

Thirteen patients with mild-moderate ileocolonic Crohn's disease received 4 g/day butyrate as enteric-coated tablets for 8 weeks. Full colonoscopy and ileoscopy were performed before and after treatment. Endoscopical and histological score, laboratory data, Crohn's disease activity index and mucosal interleukin (IL)-1beta, IL-6, IL-12, interferon-gamma, tumour necrosis factor-alpha and nuclear factor-kappa B (NF-kappaB) were assessed before and after treatment.

RESULTS

One patient withdrew from the study, and three patients did not experience clinical improvement. Among the nine patients (69%) who responded to treatment, seven (53%) achieved remission and two had a partial response. Endoscopical and histological score significantly improved after treatment at ileocaecal level (P < 0.05). Leucocyte blood count, erythrocyte sedimentation rate and mucosal levels of NF-kappaB and IL-1beta significantly decreased after treatment (P < 0.05).

CONCLUSIONS

Oral butyrate is safe and well tolerated, and may be effective in inducing clinical improvement/remission in Crohn's disease. These data indicate the need for a large investigation to extend the present findings, and suggest that butyrate may exert its action through downregulation of NF-kappaB and IL-1beta.

Rectal instillation of butyrate provides a novel clinically relevant model of noninflammatory colonic hypersensitivity in rats

BACKGROUND & AIMS

The treatment of irritable bowel syndrome (IBS), characterized by abdominal pain and bloating, is empirical and often poorly efficient. Research lacks suitable models for studying the pathophysiologic mechanisms of the colonic hypersensitivity and new pharmacologic targets. The present study aimed to develop a novel model of colonic hypersensitivity possessing several of the characteristics encountered in patients with IBS.

METHODS

Rats received enemas of a butyrate solution (8-1000 mmol/L) twice daily for 3 days. A time course was determined for colonic hypersensitivity (colorectal distention test) and referred cutaneous lumbar hyperalgesia (von Frey hairs). Macroscopic and histologic analyses were performed on colonic mucosa. The efficacy of morphine, U50488H (a kappa opioid agonist), and trimebutine on the 2 pain parameters was determined. Finally, the involvement of peptidergic C-fibers was evaluated using capsaicin-pretreated animals and treatments with calcitonin gene-related peptide (CGRP) and neurokinin 1 receptor antagonists.

RESULTS

Butyrate enemas induced a sustained, concentration-dependent colonic hypersensitivity and, to a lesser extent, a referred cutaneous mechanical hyperalgesia, particularly in female rats, but no macroscopic and histologic modifications of the colonic mucosa, as observed in patients with IBS. Both pain parameters were sensitive to morphine, U50488H, trimebutine, neonatal capsaicin treatment, and the CGRP receptor antagonist but not to the neurokinin 1 receptor antagonist.

CONCLUSIONS

These results present our noninflammatory model of chronic colonic hypersensitivity as a useful novel tool for studying IBS. The CGRP receptor antagonist-induced reduction of colonic hypersensitivity suggests that CGRP receptors may provide a promising target for treatment of IBS.

Phase II trial of the histone deacetylase inhibitor pivaloyloxymethyl butyrate (Pivanex, AN-9) in advanced non-small cell lung cancer

This multicenter phase II trial evaluated the therapeutic activity and safety profile of pivaloyloxymethyl butyrate (Pivanex, AN-9) as a single agent in refractory non-small cell lung cancer (NSCLC). Pivanex (2.34 g/m2 per day) was administered as a 6-h continuous intravenous infusion, daily for 3 days, and repeated every 21 days until disease progression. Forty-seven patients were treated. More than 90% of patients had received both a platinum compound and a taxane and 32% had received three or more prior chemotherapy regimens. The most common toxicities were transient grade 1-2 fatigue (34%), nausea (17%), and dysgeusia (11%). Three patients had partial responses (6.4 and 95%; CI 1.4-18.7%) and 14 patients had stable disease for > or =12 weeks (30%). Median survival for all patients was 6.2 months with 1-year survival of 26%. For patients who received fewer than three prior chemotherapy regimens, median survival was 7.8 months and 1-year survival was 31%. Pivanex is well tolerated and appears to be active as a single agent in patients with advanced NSCLC refractory to previous chemotherapy. Based on its therapeutic activity and favorable safety profile, further studies of Pivanex in NSCLC, particularly in combination with current chemotherapeutic agents, are warranted.

AN-9 (Titan)

Titan is developing AN-9 for the potential treatment of various cancers. AN-9 is a histone deacetylase inhibitor analog of butyric acid that causes apoptosis of cancer cells through signaling cellular differentiation. In March 2001, a phase I/II study involving patients with liver tumors was initiated. By November 2001, enrollment had been completed in a second phase II study of refractory non-small-cell lung cancer (NSCLC). In June 2003, Titan began enrollment for a phase IIb trial of AN-9 in combination with docetaxel in patients with NSCLC.

Microbial degradation products influence colon cancer risk: the butyrate controversy

All dietary fiber, by definition, escapes digestion in the small intestine and thus arrives relatively intact in the large intestine. Its fate in the large intestine depends upon the type of fiber and the colonic microflora. Highly fermentable fibers result in short chain fatty acids including butyrate, which is thought by some to be protective against colon cancer. However, not all studies support a chemopreventive effect for butyrate and the lack of agreement (particularly between in vivo and in vitro studies) on butyrate and colon cancer has been termed the "butyrate paradox." There are a number of reasons for this discrepant effect including differences between the in vitro and in vivo environments, the timing of butyrate administration, the amount of butyrate administered, the source of butyrate (usually dietary fiber) as a potential confounder, and an interaction with dietary fat. Collectively, the studies suggest that the chemopreventive benefits of butyrate depend in part on amount, time of exposure with respect to the tumorigenic process, and the type of fat in the diet.

Lack of sensitization for trimellitate, phthalate, terephthalate and isobutyrate plasticizers in a human repeated insult patch test

Two hundred and three human volunteers were tested for evidence of sensitization to several plasticizers following 3 weeks of dermal application three times a week. Tris(2-ethylhexyl)mellitate (TOTM; 1%, v/v), 2,2,4-trimethyl-1,3-pentanediol-diisobutyrate (TXIB; 1%, v/v), di(2-ethylhexyl)terephthalate (DEHT; 0.5%, v/v) and diethylphthalate (DEP; 2%, v/v) were applied to the skin of volunteers under semi-occlusive patch for 3 consecutive weeks and the reactions to a challenge application noted following a 2-week rest period. Slight erythema was observed in four individuals exposed to TOTM, two of which resolved within 96 h and one that occurred only after 96 h. Slight erythema was noted in three subjects exposed to TXIB, one of which resolved by 96 h and one that occurred only after 96 h. Two subjects had slight erythema to DEHT, one that resolved by 96 h and one that occurred only after 96 h. One reaction occurred with DEP at 96 h after challenge. Of the positive responses, one subject reacted to all test substances. No subject had a response grade of 1.0 or greater. Because of the low response, the overall conclusion is that none of the plasticizers demonstrated evidence of sensitization or irritation.

[Use of enerion in psychovegetative syndrome with pronounced asthenia]

Enerion was used in the treatment of 40 patients with psychovegetative syndrome and asthenia. Before treatment, the patients have pronounced asthenia appearances, anxiety disorders, relevant autonomic disorders, mild depression and decrease of working capacity, attention concentration and memory. The treatment was conducted as monotherapy during 28 days with enerion dosage 400 mg/day. After treatment, expression of autonomic and asthenic disorders was reduced significantly, along with improvement of psychometric and neurophysiological indices. High efficacy of the medication was detected in 75% of the patients and moderate one--in 25%. The drug was well-tolerated.

Immunotoxic and cancerostatic effects of ethyl-4-isothiocyanatobutanoate in female Lewis rats with implanted fibrosarcoma

Isothiocyanates (ITCs) have been isolated from plants. Naturally occurring and synthetic ITCs are known as effective chemopreventive agents. Ethyl 4-isothiocyanatobutanoate (E-41B) is a derivative of gamma-aminobutyric acid. Immunotoxic and canocerostatic effects of E-41B in female inbred Lewis rats implanted with experimental fibrosarcoma BP6-TU2 was evaluated in this study. On day 5 after subcutaneous application of tumor cells, animals started to be treated intraperitoneally three times a week with two different doses of E-41B: 28 and 35 mg/kg/day during 28 days. High dose of E-41B was close to maximum tolerated dose (MTD). Control groups of rats with or without tumors injected intraperitoneally only saline or 70% dimethylsulphoxide were added. Administrating of E-41B resulted in suppression of thymus, popliteal lymph node, spleen weight and spleen cellularity. Hematologic evaluation displayed decreased erythrocyte (ERY) count and level of hemoglobin (HB) in rats treated withE-41B. Immune assays--the phagocytic activity of polymorphonuclear leukocytes (PMN) and monocytes, primary antibody response and in vitro proliferative activity of spleen lymphocytes (LY) to mitogens were not significantly affected by E-41B treatment E-41B moderately decreased tumor weights, but this decrease was not statistically significant in comparison with DMSO-exposed rats with tumors. The fibrosarcoma implantation itself increased significantly spleen weight and changed hematological parameters (decreased HB, increased mean cell volume of ERY, increased leukocyte count, increased % PMN, decreased % LY, decreased % EO). Moreover, moderate decreased percentage of CD161+ positive cells (NK cells) were found in peripheral blood. Immune assays showed decline in proliferation of lymphocytes and phagocytic activity of leukocytes. Our findings indicate that administration of E-41B displayed hematoxic effect in rats implanted with fibrosarcoma. Immunotoxic effect was shown as decreased lymphoid organ weight and spleen cytotoxicity although function of immune cells was not impaired.

Sustained induction of fetal hemoglobin by pulse butyrate therapy in sickle cell disease

High levels of fetal hemoglobin (Hb F) protect from many of the complications of sickle cell disease and lead to improved survival. Butyrate and other short chain fatty acids were previously shown to increase Hb F production in erythroid cells in vitro and in animal models in vivo. However, butyrates are also known to inhibit the proliferation of many cell types, including erythroid cells. Experience with the use of butyrate in animal models and in early clinical trials demonstrated that the Hb F response may be lost after prolonged administration of high doses of butyrate. We hypothesized that this loss of response may be a result of the antiproliferative effects of butyrate. We designed a regimen consisting of intermittent or pulse therapy in which butyrate was administered for 4 days followed by 10 to 24 days with no drug exposure. This pulse regimen induced fetal globin gene expression in 9 of 11 patients. The mean Hb F in this group increased from 7.2% to 21.0% (P <.002) after intermittent butyrate therapy for a mean duration of 29.9 weeks. This was associated with a parallel increase in the number of F cells and F reticulocytes. The total hemoglobin levels also increased from a mean of 7.8 g/dL to a mean of 8.8 g/dL (P <.006). The increased levels of Hb F were sustained in all responders, including 1 patient who has been on pulse butyrate therapy for more than 28 months. This regimen, which resulted in a marked and sustained increase in Hb F levels in more than two thirds of the adult sickle cell patients enrolled in this study, was well tolerated without adverse side effects. These encouraging results require confirmation along with an appropriate evaluation of clinical outcomes in a larger number of patients with sickle cell disease.

Short-chain carboxylic-acid-stimulated, PMN-mediated gingival inflammation

This communication reviews the effects of short-chain carboxylic acids on human cells of importance to the periodontium. The central hypothesis is that these acids can alter both cell function and gene expression, and thus contribute to the initiation and prolongation of gingival inflammation. Short-chain carboxylic acids [CH3-(CH2)x-COOH, x < 3] are metabolic intermediates with a broad range of apparently paradoxical biological effects. For example, lactic acid (CH3-CHOH-COOH), a 3-carbon alpha-hydroxy-substituted acid, is widely recognized for its cariogenicity. Lactic acid, however, also occurs in tropical fruits, and is the active ingredient in a variety of anti-wrinkle creams developed by dermatologists. In marked contrast, the unsubstituted 3-carbon propionic acid (CH3-CH2-COOH) is used as a food preservative and is the active principle for one class of non-steroidal anti-inflammatory agents. Interestingly, the addition of one carbon to propionic acid dramatically changes the biological effects. The unsubstituted 4-carbon butyric acid (CH3-CH2-CH2-COOH) is used by hematologists as a de-differentiating agent for the treatment of sickle cell anemia, but by oncologists as a differentiating agent for cancer chemotherapy. Finally, acting either individually or in concert, these acids can increase vascular dilation. Clearly, these acids, while metabolically derived, have a number of very divergent activities which are cell-type-specific (Fig. 1). It may be telling that periodontal bacteria produce these acids in millimolar concentrations, and that these bacteria can be characterized by their acid production profiles. It is no less interesting that these acids occur in the gingival crevices of human subjects with severe periodontal disease at millimolar levels which are > 10-fold higher than those found in mildly diseased subjects, and are undetectable in healthy subjects. Further, when applied directly to healthy human gingiva, short-chain carboxylic acids stimulate a gingival inflammatory response and inflammatory cytokine release. At the cellular level, these acids inhibit proliferation of gingival epithelial and endothelial cells, and inhibit leukocyte apoptosis and function, but can stimulate leukocyte cytokine release. At the molecular level, these acids can stimulate neutrophil gene transcription, translation, and protein expression. Thus, the likelihood is high that these acids, in addition to their cariogenic activity, can promote and prolong gingival inflammation. Our challenge will be to identify the cell or cells of the periodontium which respond to short-chain carboxylic acids, to delineate their responses and the molecular mechanism(s) of these effects, and to categorize the aspects of the inflammatory components which damage and those which protect the host. With this information, it may be possible to begin to rationally identify and test pharmaceutical agents which diminish the harmful aspects, while enhancing the beneficial components, of the inflammatory response.

Treatment of left-sided ulcerative colitis with butyrate enemas: a controlled trial

BACKGROUND

The colonic mucosa is highly dependent upon the presence of luminal nutrients. This dependence is most marked in the distal colon. The major luminal nutrients are short chain fatty acids that are produced as a by-product of colonic fermentation of carbohydrates. Butyrate appears to be the short chain fatty acid most avidly metabolized by the colonic mucosa. It has been suggested that ulcerative colitis is, at least in part, related to an energy deficiency state of the colonic mucosa which may be secondary to impaired short chain fatty acid production, uptake or utilization. The objective of this study was to determine if butyrate given as enema therapy is effective in the treatment of active distal ulcerative colitis.

METHODS

Thirty-eight patients with distal ulcerative colitis were randomly assigned to receive nightly butyrate (n = 19) or saline/placebo (n = 19) enemas. Butyrate enemas consisted of 60 mL of 80 mM sodium butyrate titrated to a pH of 7.0. Patients were assessed clinically and endoscopically at baseline and at 3 and 6 weeks follow-up. Pre- and post-treatment mucosal biopsies were assessed histologically. Response to therapy was determined by changes in a 12-point clinical disease activity index score based on patient symptoms, endoscopic mucosal appearance and physicians' global assessment.

RESULTS

Clinical improvement was noted in seven of 19 (37%) butyrate-treated patients and nine of 19 (47%) placebo-treated patients (P = 0.51). Clinical remission was achieved in three patients in each group (16%). No toxicity was observed in either treatment arm.

CONCLUSIONS

The results suggests that once nightly 60 mL butyrate enemas (80 mmol/L) are not efficacious in the treatment of distal ulcerative colitis.

Extended therapy with intravenous arginine butyrate in patients with beta-hemoglobinopathies

BACKGROUND

Enhanced production of fetal hemoglobin lessens the severity of beta-thalassemia and sickle cell disease. Intravenous infusion of arginine butyrate can increase the number of reticulocytes containing fetal hemoglobin in patients with these disorders, and it has induced a substantial increase in hemoglobin in one patient with thalassemia. We therefore tested the efficacy of this agent in patients with beta-hemoglobinopathies.

METHODS

We treated 10 patients with severe beta-thalassemia or sickle cell disease with arginine butyrate at an initial dose of 500 mg per kilogram of body weight per day (final dose, 2000 mg per kilogram per day), 6 days per week, for a mean (+/- SD) of 10 +/- 1.2 weeks (range, 9 to 13). A hematologic response was defined as an increase in the hemoglobin concentration of at least 2 g per deciliter in patients with thalassemia and as a twofold increase in the fetal hemoglobin concentration in patients with sickle cell disease.

RESULTS

Increase in gamma-globin messenger RNA and in reticulocytes containing fetal hemoglobin but not in hemoglobin were observed in the patients with thalassemia. A small, unsustained increase in fetal hemoglobin was observed in two patients with sickle cell disease. Drug toxicity was minimal at standard doses. One patient had a grand mal seizure after inadvertently receiving 2000 mg of arginine butyrate per kilogram over a period of six hours.

CONCLUSIONS

Ten weeks of intravenous arginine butyrate did not produce a hematologic response in 10 patients with either severe beta-thalassemia or sickle cell disease.

The effect of a prostaglandin DP-receptor partial agonist (192C86) on platelet aggregation and the cardiovascular system in healthy volunteers

1. PGD2 (DP)-receptors mediate inhibition of platelet aggregation and vasodilatation. If receptor reserve were greater on platelets it might be possible to separate these effects. To determine whether such a difference in receptor reserve exists, we have examined the effects of a highly selective DP-receptor partial agonist 192C86 on platelet aggregation and the cardiovascular system in healthy volunteers. 2. Using an open, dose-escalating study design, four male volunteers received constant rate intravenous infusions of 192C86 for up to 60 min. Ex vivo platelet aggregation to ADP and collagen in platelet-rich plasma (PRP) and whole blood (WB) was studied at baseline, after 15, 30 and 60 min of each infusion and at 180 min post-infusion. Heart rate (HR), systolic and diastolic (DBP) blood pressure were measured at frequent intervals. Adverse experiences were monitored by checklist. Facial flushing was assessed by the volunteer using a visual analogue scale, by an observer using a numerical scale and by full-face colour photographs. Blood was taken for assay of plasma 192C86 concentrations by radio-immunoassay (r.i.a.). 3. 192C86 (0.007-0.058 micrograms kg-1 min-1) inhibited platelet aggregation to ADP and collagen both in PRP and WB in a dose-dependent manner. However, this was always accompanied by a decrease in DBP, increase in HR and facial flushing. Plasma concentrations of 192C86 were at or below the limits of sensitivity of the r.i.a. (0.5 ng ml-1). 4. The highest infusion rate was stopped after 20 min due to symptomatic hypotension on standing.(ABSTRACT TRUNCATED AT 250 WORDS)

Influence of butyrate on lipid metabolism, survival, and differentiation of colon cancer cells

The present work was designed to study the differentiating effect of butyrate on LS174T cells after modification of their lipids with long-chain fatty acid (LCFA) supplementation. The LCFAs 18:1(n-9), 18:2(n-6), 20:4(n-6), 20:5(n-3), and 22:6(n-3) bound to added to the media of confluent cells for eight days. The fatty acid-to-albumin ratio was 3:1. The concentration of fatty acids in the media was 100 microM. On the last day, half of the flasks were treated with 2 mM butyrate. The data indicate that supplementation with polyunsaturated LCFAs having 20-22 carbon atoms resulted in a significant reduction in cell density and viability, whereas all LCFA supplementation reduced differentiation as measured by alkaline phosphatase activity. Butyrate treatment increased the density, viability, and differentiation of the tumor cells. The effect of butyrate on differentiation was mainly with cells supplemented with 18:1, 20:5, and 22:6. In the absence of LCFA supplementation, butyrate reduced the concentration of 22:5(n-6) in the cellular lipids. Also, butyrate modified the LCFAs incorporated in cells supplemented with 18:2 and 20:5, with changes occurring in 20:5(n-3), 22:5(n-3), and 22:5(n-6). Thus the present study suggests an interaction between butyrate and LCFA on differentiation and LCFA metabolism of human colon cancer cells.

Phenoxy herbicides and soft-tissue sarcomas in female rice weeders. A population-based case-referent study

A population-based case-referent study was conducted in an area of northern Italy where rice growing is the predominant agricultural activity and phenoxy herbicides have been used since 1950. Manual rice weeding was formerly performed by a seasonal female working population; in the early 1950s these women were concurrently exposed to chemical herbicides. Sixty-eight persons representing incident and histologically revised cases (31 women) and 158 population referents (73 women) were interviewed. The cases were histologically confirmed independently by two blinded pathologists, and exposure to phenoxy herbicides was assessed by two blinded pesticide researchers. An age-adjusted odds ratio of 0.91 was found for the living men (with suspect exposures; no man diagnosed as a case had been exposed with certainty to phenoxy herbicides). Among the living women the relative risk was 2.7 (90% confidence interval 0.59-12.37), and it further increased when attention was restricted to women exposed in the whole 1950-1955 period and to younger age groups.

Reduction in mitogenic response of bovine lymphocytes by ketone bodies

The effect of toxic or subtoxic concentrations of ketone bodies (acetone, beta-hydroxybutyrate, acetoacetate) in blood on function of bovine lymphocytes was studied in vitro. Lymphocytes separated from peripheral bovine blood were distributed into the wells of Linbro Microtiter plates containing control medium and test medium with various concentrations of ketones and/or phytohemagglutinin. The mitogenic response of lymphocytes was measured by incorporation of [3H]thymidine into DNA of lymphocytes. Toxic and subtoxic concentrations of beta-hydroxybutyrate or the toxic concentration of acetoacetate significantly affected the mitogenic response of bovine lymphocytes. The reduction in the mitogenic response also occurred when lymphocytes were only preincubated for 2 hours or longer with beta-hydroxybutyrate or acetoacetate. The presence of the toxic concentration of acetone in the medium did not affect the mitogenic stimulation of lymphocytes.

Present status of clofibrate therapy in ophthalmology

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