DOI: 10.14457/tu.the.2017.1315
title: The clinical safety and pharmacokinetics of Sahastara remedy ethanolic extract capsules in healthy volunteers (clinical trial phase 1)

description: The Sahastara (SHT) remedy is a Thai traditional medicine that has long been used to treat muscle and joint pain. The SHT remedy was published in Thailand National List of Essential Medicine (NLEM). It contains 21 medicinal plants. The main ingredients are pepper (Piper nigrum Linn.) and long pepper (Piper retrofractum Vahl.) which have piperine as a major compound. The SHT remedy extract has high anti-inflammatory activity by inhibition of NO and PGE2 (IC50 = 2.81 µg/ml and 16.97±1.16 µg/ml, respectively). The SHT remedy extract did not show acute and chronic toxicity in the rat model. Moreover, the SHT remedy powder drug has good efficacy and safety to treat patients of knee osteoarthritis. This information indicated that SHT remedy has potential to be developed as a modern drug in extracted form. Thus, this study was the first investigation on clinical safety and pharmacokinetics of SHT remedy extract capsules in healthy volunteers.The study was investigated to be in 2 parts including preclinical part and clinical part. The preclinical part was a study on quality standards of the SHT remedy extract and capsules. The SHT remedy was extracted by 95% ethanol maceration. The anti-inflammatory activity with NO production inhibition by Griess reagent assay was performed as biological activity assessment while total phenolic content by Folin-Ciocalteau’s reagent assay and the values of piperine content which was measured by HPLC were performed as chemical content assessment. The SHT remedy extract capsules were also quality-tested according to Thai herbal pharmacopeia including the moisture test (loss on drying), contamination test, weight variations and disintegration time. The SHT remedy extract capsules were kept in accelerated conditions (40 °C and 75%RH) for 0, 15, 30, 60, 90, 120, 150 and 180 days according to stability test method of ICH harmonized tripartite guideline. Then, anti-inflammatory activity by NO inhibition and piperine content measurement by HPLC were performed with SHT remedy extract capsules at each time interval, compared with Day 0 which confirmed that anti-inflammatory activity and chemical content were not changed.The preclinical results demonstrated that SHT remedy ethanolic extract has percentage of yield as 9.80%. The SHT remedy ethanolic extract had good quality which passed all standard criteria including anti-inflammatory activity by NO inhibition (IC50=6.274 µg/ml), total phenolic compound (42.69±3.18 mg.GAE/g.extract) and piperine content (224.94 mg/g.extract). The SHT remedy ethanolic extract and its capsules also passed the standard criteria including moisture test, contaminant test, weight variations and disintegration time. The stability test of SHT remedy ethanolic extract capsules not only show no significant difference from day 0 but also they passed the acceptable criteria of SHT remedy extracts including anti-inflammatory activity and chemical content. These data meant that SHT remedy ethanolic extract capsules could be kept at room temperature for 2 years which covered the period of this study.In clinical part, forty-eight healthy volunteers of both sexes and between 20-45 years of age were screened by history taking, complete physical examination and laboratory tests including complete blood count (CBC), lipid profile, renal function test, liver functions test, blood electrolyte and urine analysis. The healthy volunteers were included in the study. Volunteers who had severe peptic ulcer, high blood pressure (systolic &gt;140 mm.Hg. and diastolic &gt; 90 mm.Hg.), impaired renal and liver functions were excluded from the study.Twenty-four eligible volunteers were recruited into the clinical safety trial of SHT remedy ethanolic extract capsules in healthy volunteers. They were divided into 2 dose groups (6 males and 6 females each group) and were assigned to take 1 or 2 capsules of 100 mg of SHT extract orally 3 times a day before meals for 28 days. The follow-up including history taking, complete physical examination, liver function test and renal function test were performed every 14 days for 28 days and extended for 14 days after the volunteers finished taking SHT ethanolic extract capsules.The SHT remedy ethanolic extract capsules in clinical trial phase 1 in healthy volunteers were quite safe for continuously use in humans for 28 days. The results show that the most common adverse events of 300 mg/day and 600 mg/day dose groups were abdominal discomfort (66.67% and 58.33% respectively). The severity effect was mild to moderate grade. Laboratory results show no significant difference between dose groups for AST, ALT, ALP, BUN and creatinine inclusively. (P&gt;0.05) In addition, all values on 28 days have no significant different when compared with values at day 0 for both dose groups.   For pharmacokinetics study, twenty-four eligible volunteers were recruited into this study. The piperine content in SHT extract capsule with single oral dose in healthy volunteers were determined by HPLC. They were also divided into 2 dose groups (6 males and 6 females each group). They were assigned to take 100 or 200 mg of SHT remedy ethanolic extract capsules. Then, they were appointed for admission to hospital. The volunteers were required to have had nothing via a mouth at least 8 hours (fasting) before receiving SHT remedy ethanolic extract capsules. The volunteers received a single oral dose depending on which dose that they were assigned, 1 capsule for 100 mg dose or 2 capsules for 200 mg dose.  Blood was collected in heparin tube before taking medicine (time 0) and after taking medicine as follows by: 0.5, 1, 2, 4, 6, 8, 12, 18, 24 and 48 hours. All urine was collected over 24 hours after taking SHT capsules. Then, 100 ml sample was taken for piperine measurement. The safety characteristic and symptoms were monitored over the whole study. The piperine concentration in blood and urine were determined by LC/MS/MS.The pharmacokinetics of piperine following SHT administration showed rapid absorption and slowly excretion. The peak of piperine concentration was 3,766 ng/mL at 4.46 hours and 6,586 ng/mL at 1.88 hours in SHT 100 mg and 200 mg respectively. The SHT ethanolic extract capsules 200 mg had double the volume of distribution of piperine compared to 100 mg group (0.14 and 0.07 L/kg respectively). The piperine concentration in plasma was slightly decreased to baseline within 48 hours. The elimination half-life of piperine in 200 mg group showed approximately a 2-fold longer half-life than group of 100 mg (19.48 and 8.74 hours respectively). However, the piperine was not detectable in urine. A secondary maximum concentration was observed in this study. This phenomenon is common in enterohepatic recirculation.From the present study it can be concluded that SHT remedy ethanolic extract capsules passed the acceptable standard criteria. It has a shelf-life of 2 years at room temperature which covered the period of the study. The SHT remedy was very safe to continue use in humans for 28 days. The SHT remedy did not show serious side effects and did not affect liver and renal functions in healthy volunteers. The piperine in SHT remedy ethanolic extract showed dose dependent manner the double dose of SHT can increase absorption, maximum concentration and residual time of piperine in human. However, this study suggested 100 mg of SHT dose 3 times a day was an appropriated dose to use in humans because it has less side effect than 200 mg dose which was also acceptable efficacy. Moreover, SHT dose was taken for 3 times a day can cover the half-life of piperine in SHT remedy ethanolic extract capsules.