Real-world use of avatrombopag in patients with chronic liver disease and thrombocytopenia undergoing a procedure.

The phase 4 observational cohort study assessed the effectiveness and safety of the thrombopoietin receptor agonist avatrombopag in patients with chronic liver disease (CLD) and thrombocytopenia undergoing a procedure. Patients with CLD may have thrombocytopenia, increasing the risk of periprocedural bleeding. Prophylactic platelet transfusions used to reduce this risk have limitations including lack of efficacy and transfusion-associated reactions. Prophylactic thrombopoietin receptor agonists have been shown to increase platelet counts and decrease platelet transfusions. Effectiveness was assessed by change from baseline in platelet count and proportion of patients needing a platelet transfusion. Safety was assessed by monitoring adverse events (AEs). Of 50 patients enrolled, 48 were unique patients and 2 patients were enrolled twice for separate procedures. The mean (standard deviation) change in platelet count from baseline to procedure day was 41.1 × 109/L (33.29 × 109/L, n = 38), returning to near baseline at the post-procedure visit (change from baseline -1.9 × 109/L [15.03 × 109/L], n = 11). The proportion of patients not requiring a platelet transfusion after baseline and up to 7 days following the procedure was 98% (n = 49). Serious AEs were infrequent (n = 2 [4%]). No treatment-emergent AEs were considered related to avatrombopag. There were 2 mild bleeding events, no thromboembolic events or deaths, and no patients received rescue procedures (excluding transfusions). This study found that in a real-world setting, treatment with avatrombopag was well tolerated, increased the mean platelet count by procedure day, and reduced the need for intraoperative platelet transfusions in patients with CLD and thrombocytopenia.

Avatrombopag ethnic sensitivity analysis in chronic liver disease and thrombocytopenia patients: individual-level pooled analysis.

Introduction: Few data have been published on the ethnic sensitivity of effectiveness, pharmacokinetics (PK), and pharmacodynamics (PD) of avatrombopag for the management of thrombocytopenia in patients with chronic liver disease (CLD). Methods: An ethnic sensitivity analysis was performed based on the results from two phase III studies (ADAPT-1 and ADAPT-2), with a primary endpoint of the proportion of patients without the requirement of platelet transfusion or rescue treatment for bleeding after randomization to 7 days following a scheduled procedure, and three phase I studies in healthy subjects. Cochran-Mantel-Haenszel and Fisher's exact tests were used to compare the differences in effectiveness in different ethnicities and overall population. Results: In total, 435 patients (placebo, n = 158; avatrombopag, n = 277) were stratified into various ethnic groups: 121 East Asians, including the subgroup of 27 Chinese, and 259 Caucasians. The proportion of patients who did not receive a platelet transfusion and those with a platelet count ⩾50 × 109/L in the avatrombopag 40 and 60 mg groups were higher than that of placebo for all ethnicities and in the overall population. Statistical significance was obtained in the overall population and for all ethnicities other than Chinese patients, a group with a very small sample size. No significant difference was observed in the proportion of responders in each ethnic group compared to overall population (p > 0.05). The incidence of adverse events in East Asians was similar to that in both Caucasians and the overall population. Conclusion: Avatrombopag was effective and safe in the management of thrombocytopenia in Chinese patients with CLD. Ethnicity does not appear to influence the efficacy, safety, PK, or PD of avatrombopag.

Avatrombopag for chemotherapy-induced thrombocytopenia in patients with non-haematological malignancies: an international, randomised, double-blind, placebo-controlled, phase 3 trial.

BACKGROUND: Chemotherapy-induced thrombocytopenia is common and causes chemotherapy dose reductions or treatment delays, bleeding, and suboptimal oncological outcomes. We aimed to evaluate avatrombopag, a thrombopoietin receptor agonist that increases platelet counts, in patients with non-haematological cancer and platelet counts lower than 50 ×109 cells per L. METHODS: In this randomised, double-blind, placebo-controlled, phase 3 study, patients aged 18 years or older at 71 hospitals or cancer treatment centres in China, Hungary, Poland, Russia, Serbia, Ukraine, and the USA and with ovarian, bladder, or lung cancer receiving chemotherapy who had severe thrombocytopenia were randomly assigned (2:1) to oral avatrombopag 60 mg or oral placebo once daily given 5 days before and after chemotherapy, with randomisation stratified by number of chemotherapy drugs used. Patients, investigators, and data collectors were masked to group allocation. Eligibility required two previous lines of chemotherapy or fewer, an ECOG performance status of 2 or less, and no previous history of chemotherapy-induced thrombocytopenia. The composite primary endpoint was the proportion of responders not requiring platelet transfusion or either a 15% or more chemotherapy dose reduction or a 4-day or more chemotherapy delay due to thrombocytopenia following study treatment until the start of the subsequent cycle. Analyses were done on the intention-to-treat and per protocol populations. Safety was analysed in all patients who received at least one dose of avatrombopag. The trial is registered with ClinicalTrials.gov, NCT03471078, and has been completed. FINDINGS: Between Oct 12, 2018, and June 28, 2020, 122 patients were enrolled and randomly assigned to receive avatrombopag (n=82) or placebo (n=40). Median follow-up was 31 days (IQR 22-61). Similar proportions of patients reached the primary endpoint in the avatrombopag and placebo groups (intention-to-treat: 57 [70%, 95% CI 58-79] of 82 vs 29 [73%, 95% CI 56-85] of 40; difference -3·0% (95% CI -21·6 to 15·6); p=0·72; per protocol: 51 [85%, 95% CI 73-93] of 60 vs 27 [84%, 95% CI 67-95] of 32; 0·6% (95% CI -20·8 to 22·1); p=0·96). 15 (18%) of 82 patients had serious adverse events in the avatrombopag group and eight (20%) of 40 in the placebo group, of which thrombocytopenia was most common (4 [5%] of 82 and 4 [10%] of 40 patients). Common grade 3-4 treatment-emergent adverse events were neutropenia (22 [27%] of 82 and 16 [40%] of 40 patients), leukopenia (19 [23%] of 82 and 5 [13%] of 40), anaemia (16 [20%] of 82 and 9 [23%] of 40), and thrombocytopenia (16 [20%] of 82 and 14 [35%] of 40). Most adverse events were considered unrelated to study drug. No treatment-related deaths were reported. INTERPRETATION: In this population of patients with non-haematological malignancies who are relatively chemotherapy naive, chemotherapy-induced thrombocytopenia treatment outcomes were similar between the avatrombopag and placebo groups. Given its safety and ability to augment platelet counts in patients with chemotherapy-induced thrombocytopenia, evaluation of avatrombopag in populations with more persistent chemotherapy-induced thrombocytopenia is warranted. FUNDING: Dova Pharmaceuticals, a Sobi company.

Phase 3 randomised study of avatrombopag, a novel thrombopoietin receptor agonist for the treatment of chronic immune thrombocytopenia.

Avatrombopag, an oral thrombopoietin receptor agonist, was compared with placebo in a 6-month, multicentre, randomised, double-blind, parallel-group Phase 3 study, with an open-label extension phase, to assess the efficacy and safety of avatrombopag (20 mg/day) in adults with chronic immune thrombocytopenia (ITP) and a platelet count <30 × 109 /l (ClinicalTrials.gov identifier NCT01438840). The primary endpoint was the cumulative number of weeks of platelet response (platelet count ≥50 × 109 /l) without rescue therapy for bleeding; secondary endpoints included platelet response rate at day 8 and reductions in the use of concomitant medications. Amongst the 49 patients randomised, avatrombopag (N = 32) was superior to placebo (N = 17) in the median cumulative number of weeks of platelet response (12·4 vs. 0·0 weeks, respectively; P < 0·0001). At day 8, a greater platelet response rate was also observed for patients treated with avatrombopag compared with placebo (65·63% vs. 0·0%; P < 0·0001), and use of concomitant ITP medications was also reduced amongst patients receiving avatrombopag. The safety profile of avatrombopag was consistent with Phase 2 studies; the most common adverse events were headache and contusion. Overall, avatrombopag was well tolerated and efficacious for the treatment of chronic ITP.

Metabolism, Excretion, and Mass Balance of Solithromycin in Humans.

Solithromycin, a novel macrolide and the first fluoroketolide, is being developed as a therapy for community-acquired bacterial pneumonia, with a distinct mechanism that provides activity against macrolide-resistant bacteria. The pharmacokinetics, metabolism, and excretion of solithromycin were studied in healthy male subjects after oral administration of a single 800-mg (∼100-µCi) dose of [14C]solithromycin. Solithromycin was well tolerated, and absorption from the solution occurred with a median time to peak concentration of 4.0 h. Solithromycin and the total radioactivity had similar profiles with no long-lived metabolites. The whole-blood total radioactivity was approximately 75% of the plasma total radioactivity. Recovery was essentially complete (mean, 90.6%), with 76.5% and 14.1% of the dose recovered in feces and urine, respectively. Unchanged solithromycin (CEM-101) was the predominant circulating radioactive component in plasma (77% of the total radioactivity area under the concentration-time curve [AUC]), with two minor plasma metabolites, CEM-214 and CEM-122 (N-acetyl-CEM-101), each accounting for approximately 5% of the total radioactivity. Urinary excretion was predominantly like that of the parent. Solithromycin was primarily eliminated in the feces after extensive metabolism via a complex metabolic pathway with CEM-262 as the major constituent (27.36% of the administered dose). Overall oxidative pathways, presumably carried out mostly by CYP3A4, represented the majority of the metabolism, with N-acetylation present to a lesser extent. No disproportionate human metabolites were observed.

Development of an Adult Physiologically Based Pharmacokinetic Model of Solithromycin in Plasma and Epithelial Lining Fluid.

Solithromycin is a fluoroketolide antibiotic under investigation for community-acquired bacterial pneumonia (CABP). We developed a whole-body physiologically based pharmacokinetic (PBPK) model for solithromycin in adults using PK-Sim and MoBi version 6.2, which incorporated time-dependent CYP3A4 auto-inhibition. The model was developed and evaluated using plasma and epithelial lining fluid (ELF) concentration data from 100 healthy subjects and 22 patients with CABP (1,966 plasma, 30 ELF samples). We performed population simulations and calculated the number of observations falling outside the 90% prediction interval. For the oral regimen (800 mg on day 1 and 400 mg daily on days 2-5) that was evaluated in phase III studies, 11% and 23% of observations from healthy adults fell outside the 90% prediction interval for plasma and ELF, respectively. This regimen should be effective because ≥97% of simulated adults achieved area under the concentration vs. time curve (AUC) to minimum inhibitory concentration ratios associated with a log10 colony forming unit reduction in ELF.

Solithromycin, a novel macrolide, does not prolong cardiac repolarization: a randomized, three-way crossover study in healthy subjects.

BACKGROUND: Macrolide antibiotics may cause QT prolongation. OBJECTIVES: To study the QT effect of a novel macrolide, solithromycin. METHODS: This was a thorough QT study with a three-way crossover design performed in healthy male and female subjects to evaluate the ECG effects of a novel macrolide, solithromycin. Forty-eight subjects were randomized to receive 800 mg of intravenous (iv) solithromycin, 400 mg of oral moxifloxacin and placebo in three separate treatment periods. Continuous 12 lead ECGs were recorded at a pre-dose baseline and serially after drug administration for 24 h. RESULTS: After the 40 min infusion of 800 mg of solithromycin, the geometric mean solithromycin peak plasma concentration (Cmax) reached 5.9 (SD: 1.30) µg/mL. Solithromycin infusion caused a heart rate increase with a peak effect of 15 bpm immediately after the end of the infusion. The change-from-baseline QTcF (ΔQTcF) was similar after dosing with solithromycin and placebo and the resulting placebo-corrected ΔQTcF (ΔΔQTcF) for solithromycin was therefore small at all timepoints with a peak effect at 4 h of only 2.8 ms (upper bound of the 90% CI: 4.9 ms). Using a linear exposure-response model, a statistically significant, slightly negative slope of -0.86 ms per ng/mL (90% CI: -1.19 to -0.53; P = 0.0001) was observed with solithromycin. The study's ability to detect small QT changes was confirmed by the moxifloxacin response. Solithromycin did not have a clinically meaningful effect on the PR or QRS interval. CONCLUSIONS: The study demonstrated that solithromycin, unlike other macrolide antibiotics, does not cause QT prolongation.

SOLITAIRE-IV: A Randomized, Double-Blind, Multicenter Study Comparing the Efficacy and Safety of Intravenous-to-Oral Solithromycin to Intravenous-to-Oral Moxifloxacin for Treatment of Community-Acquired Bacterial Pneumonia.

BACKGROUND: Solithromycin, a novel macrolide antibiotic with both intravenous and oral formulations dosed once daily, has completed 2 global phase 3 trials for treatment of community-acquired bacterial pneumonia. METHODS: A total of 863 adults with community-acquired bacterial pneumonia (Pneumonia Outcomes Research Team [PORT] class II-IV) were randomized 1:1 to receive either intravenous-to-oral solithromycin or moxifloxacin for 7 once-daily doses. All patients received 400 mg intravenously on day 1 and were permitted to switch to oral dosing when clinically indicated. The primary objective was to demonstrate noninferiority (10% margin) of solithromycin to moxifloxacin in achievement of early clinical response (ECR) assessed 3 days after first dose in the intent-to-treat (ITT) population. Secondary endpoints included demonstrating noninferiority in ECR in the microbiological ITT population (micro-ITT) and determination of investigator-assessed success rates at the short-term follow-up (SFU) visit 5-10 days posttherapy. RESULTS: In the ITT population, 79.3% of solithromycin patients and 79.7% of moxifloxacin patients achieved ECR (treatment difference, -0.46; 95% confidence interval [CI], -6.1 to 5.2). In the micro-ITT population, 80.3% of solithromycin patients and 79.1% of moxifloxacin patients achieved ECR (treatment difference, 1.26; 95% CI, -8.1 to 10.6). In the ITT population, 84.6% of solithromycin patients and 88.6% of moxifloxacin patients achieved clinical success at SFU based on investigator assessment. Mostly mild/moderate infusion events led to higher incidence of adverse events overall in the solithromycin group. Other adverse events were comparable between treatment groups. CONCLUSIONS: Intravenous-to-oral solithromycin was noninferior to intravenous-to-oral moxifloxacin. Solithromycin has potential to provide an intravenous and oral option for monotherapy for community-acquired bacterial pneumonia. CLINICAL TRIALS REGISTRATION: NCT01968733.

A Phase 2 Trial of Oral Solithromycin 1200 mg or 1000 mg as Single-Dose Oral Therapy for Uncomplicated Gonorrhea.

BACKGROUND: Progressive resistance to antimicrobial agents has reduced options for gonorrhea therapy worldwide. Solithromycin (CEM-101) is a novel oral fluoroketolide antimicrobial with substantial in vitro activity against Neisseria gonorrhoeae. METHODS: We conducted a phase 2 trial of 2 oral doses of solithromycin (1200 and 1000 mg) for treatment of uncomplicated gonorrhea. RESULTS: A total of 59 participants were enrolled and treated in this trial; 28 participants received 1200 mg of solithromycin and 31 received 1000 mg. Forty-six (78%) participants had positive cultures for N. gonorrhoeae at the time of enrollment: 24 of the 28 persons (86%) who received 1200 mg of oral solithromycin, and 22 of 31 (71%) who received 1000 mg. In addition, 8 participants had positive pharyngeal gonococcal cultures, and 4 had positive rectal cultures. All patients with positive cultures for N. gonorrhoeae were cured at all sites of infection. Chlamydia trachomatis and Mycoplasma genitalium coinfections were evaluated using nucleic acid amplification tests and were negative at 1 week of follow-up in 9 of 11 (82%) participants positive for C. trachomatis and 7 of 10 (70%) participants positive for M. genitalium. Mild dose-related gastrointestinal side effects (nausea, loose stools, vomiting) were common but did not limit therapy. CONCLUSIONS: Oral single-dose solithromycin, in doses of 1000 mg and 1200 mg, was 100% effective for treatment of culture-proven gonorrhea at genital, oral, and rectal sites of infection and is a promising new agent for gonorrhea treatment. CLINICAL TRIALS REGISTRATION: NCT01591447.

Safety and Pharmacokinetics of Solithromycin in Subjects with Hepatic Impairment.

Solithromycin, a new macrolide and the first fluoroketolide, is in late-stage clinical development and, like older macrolides, is primarily metabolized and excreted through liver-dependent mechanisms. This study evaluated the safety and pharmacokinetics of solithromycin in patients with chronic liver disease. This open-label, multiple-dose study in subjects with hepatic impairment and in healthy control subjects (matched for age, weight, and sex) enrolled 8 Child-Pugh class A (mild), 8 class B (moderate), and 8 class C (severe) patients and 9 healthy controls. Subjects (n = 33) received one 800-mg dose on day 1 followed by once-daily doses of 400 mg on days 2 through 5. The most commonly reported adverse events were mild diarrhea and mild headache, and no significant differences were noted between hepatically impaired subjects and healthy controls. The pharmacokinetics of plasma solithromycin in subjects with mild and moderate impairment was similar to that in control subjects. In subjects with severe impairment, total exposure to solithromycin at steady state (area under the plasma concentration-time curve [AUC0-tau]) was decreased compared to that in control subjects, which may have been related to the higher body mass index of individuals in this group. No greater accumulation was noted in any hepatically impaired cohort on day 5 compared to that in control subjects. No decrease in dosage is therefore needed when administering solithromycin to patients with mild, moderate, or severe hepatic impairment. Solithromycin was well tolerated in this patient population, and no significant differences in safety, compared to healthy controls, were noted.

Randomized, double-blind, multicenter phase 2 study comparing the efficacy and safety of oral solithromycin (CEM-101) to those of oral levofloxacin in the treatment of patients with community-acquired bacterial pneumonia.

Solithromycin, a new macrolide, and the first fluoroketolide in clinical development, with activity against macrolide-resistant bacteria, was tested in 132 patients with moderate to moderately severe community-acquired bacterial pneumonia (CABP) in a multicenter, double-blind, randomized phase 2 study. Patients were enrolled and randomized (1:1) to either 800 mg solithromycin orally (PO) on day 1, followed by 400 mg PO daily on days 2 to 5, or 750 mg levofloxacin PO daily on days 1 to 5. Efficacy outcome rates of clinical success at the test-of-cure visit 4 to 11 days after the last dose of study drug were comparable in the intent-to-treat (ITT) (84.6% for solithromycin versus 86.6% for levofloxacin) and microbiological-intent-to-treat (micro-ITT) (77.8% for solithromycin versus 71.4% for levofloxacin) populations. Early response success rates at day 3, defined as improvement in at least two cardinal symptoms of pneumonia, were also comparable (72.3% for solithromycin versus 71.6% for levofloxacin). More patients treated with levofloxacin than with solithromycin experienced treatment-emergent adverse events (TEAEs) during the study (45.6% versus 29.7%). The majority of TEAEs were mild or moderate gastrointestinal symptoms and included nausea (1.6% for solithromycin; 10.3% for levofloxacin), diarrhea (7.8% for solithromycin; 5.9% for levofloxacin), and vomiting (0% for solithromycin; 4.4% for levofloxacin). Six patients, all of whom received levofloxacin, discontinued the study drug due to an adverse event. Solithromycin demonstrated comparable efficacy and favorable safety relative to levofloxacin. These findings support a phase 3 study of solithromycin for the treatment of CABP. (This study has been registered at ClinicalTrials.gov under registration no. NCT01168713.).

Thoracic and lumbar paravertebral blocks for outpatient lithotripsy.

Paravertebral nerve block has been used for a variety of surgical procedures to provide unilateral anesthesia and postoperative analgesia. We report the successful application of this regional anesthesia modality for outpatient lithotripsy. Preoperatively, thoracic and lumbar paravertebral nerve blocks with 0.5% ropivacaine were placed with ultrasound and nerve stimulator guidance for two patients with ureteral calculi. One patient scheduled for cystoscopy and ureteroscopy with laser lithotripsy received general anesthesia intraoperatively. The second patient underwent extracorporeal shock wave lithotripsy with propofol intravenous sedation. Postoperatively, both patients reported pain scores of zero (Visual Analog Scale) for 24 hours and required no opioid rescue analgesia.