Clinical Pharmacology for Orlynvah
Mechanism Of Action
ORLYNVAH is a combination of sulopenem etzadroxil, a penem antibacterial drug [see Microbiology] and probenecid, a renal tubular inhibitor. Probenecid inhibits OAT3-mediated renal clearance of sulopenem, resulting in increased plasma concentrations of sulopenem.
Pharmacodynamics
Similar to other beta-lactam antimicrobial drugs, the percentage of time that unbound plasma concentrations of sulopenem exceed the sulopenem minimum inhibitory concentration (MIC) against the infecting organism has been shown to best correlate with efficacy in in vitro models of infection.
Cardiac Electrophysiology
At a concentration of 40 times or greater than that achieved after a single oral administration of ORLYNVAH, sulopenem does not prolong the QTc interval to a clinically relevant extent.
Pharmacokinetics
Sulopenem etzadroxil is a prodrug [see Microbiology]. The pharmacokinetics of sulopenem and probenecid were characterized in healthy subjects following single oral administration of ORLYNVAH (500 mg sulopenem etzadroxil and 500 mg probenecid). Pharmacokinetic parameters are presented in Table 3 as mean [coefficient of variation (%CV)] unless otherwise specified.
Table 3. Pharmacokinetics of Sulopenem and Probenecid in Plasma after Single Oral Dose Administration of ORLYNVAH in Healthy Subjects
| Parameter |
Sulopenem |
Probenecid |
| Fasted |
Feda |
Fasted |
Feda |
| General Information |
| Exposureb |
| Cmax |
1.84 (39.1) |
2.66 (43.6) |
41.2 (38.2) |
30.4 (30.9) |
| AUC0-inf |
4.85 (25.3) |
7.41 (22.7) |
255 (35.6) |
237 (35.2) |
| Dose Proportionalityb |
Dose Proportional |
unknown |
| Accumulation |
None |
unknown |
| Absorption |
| Bioavailability |
40% |
64% |
unknown |
| TmaxMedian (range) |
1.0 (0.5 to 3.0) |
2.0 (1.0 -3.0) |
3.0 (1.0 – 10.0) |
2.0 (1.50 to 6.0) |
| Effect of Food |
| High fat meala (Fed:Fasted ratio) |
Cmax |
Increased 45% |
Decreased 27% |
| AUC0-inf |
Increased 48% |
Decreased 8% |
| Distribution |
| Apparent Volume of Distribution (Liters) (mean (SD)) |
134 (51.36) |
92.09 (33.43) |
8.81 (3.91) |
11.94 (3.46) |
| Protein Bindingc |
11% |
Unknown |
| Elimination |
| Half-Life (hours) (mean (SD)) |
1.18 (0.24) |
1.28 (0.49) |
2.93 (0.83) |
3.83 (0.50) |
| Apparent Clearance (L/hour) (mean (SD)) |
77.6 (19.77) |
50.55 (11.60) |
2.06 (0.70) |
2.22 (0.76) |
| Metabolism |
| Primary Pathway |
Sulopenem etzadroxil is hydrolyzed by esterases to active sulopenem then further metabolized by hydrolysis followed by dehydrogenation |
unknown |
| Major Metabolites |
M1a and M1bd
(inactive) |
unknown |
| Excretione |
| Feces |
44.3%
(26.9% unchanged) |
unknown |
| Urine |
40.8%
(3.1% unchanged) |
unknown |
Abbreviations: Cmax = maximum plasma concentration; AUC= area under the time concentration curve; Tmax = time to peak concentration
a A high fat meal is 800-1000 calories, approximately 50% of total calories from fat
b No clinically significant sulopenem divergence from dose-proportionally was observed over a dose range of 400 mg to 2000 mg (0.8 to 4 times the approved recommended sulopenem etzadroxil dosage)
c Independent of concentration over a range of 1 to 100 µg/mL
d Sulopenem, M1a and M1b, accounted for 32%, 21.8% and 43.6% of circulating radioactivity, respectively
e After a single oral dose of radiolabeled sulopenem etzadroxil 2000 mg healthy adult subjects |
Specific Populations
No clinically significant differences in the pharmacokinetics of sulopenem were observed based on age, sex or weight. The effect of hepatic impairment on sulopenem pharmacokinetics is unknown.
Patients With Renal Impairment
Sulopenem mean plasma AUC0-inf increased by 2-fold in patients with mild (CrCL 60 to 89 mL/min), estimated by Cockcroft-Gault equation), by 3-fold in patients with moderate (CrCL 30 to 59 mL/min) and by 7.4-fold in patients with severe (CrCL15 to 29 mL/min) renal impairment following administration of 1000 mg oral sulopenem etzadroxil (not a recommended dosing regimen) [see DOSAGE AND ADMINISTRATION]. The effect of kidney failure (CrCL<15 mL/min) or hemodialysis on sulopenem pharmacokinetics is unknown.
Drug Interaction Studies
Clinical Studies
Effect of Other Drugs on the Pharmacokinetics of ORLYNVAH:
No clinically significant differences in the pharmacokinetics of sulopenem were observed when ORLYNVAH was administered concomitantly with oral itraconazole (P-gp inhibitor), pantoprazole (gastric-acid reducing agent) or aluminum hydroxide (gastric acid-reducing agent).
No clinically significant differences in the pharmacokinetics of valproic acid were observed when used concomitantly with ORLYNVAH. Although there are case reports in the published literature that suggest concomitant use of carbapenems result in a reduction in valproic acid concentrations, the probenecid component of ORLYNVAH appears to counteract any potential effect of sulopenem on valproic acid [see DRUG INTERACTIONS].
Effect of ORLYNVAH on the Pharmacokinetics of Other Drugs:
Coadministration of multiple doses of 500 mg sulopenem etzadroxil with valproic acid decreased valproic acid plasma AUC0-tau and Cmax by approximately 25% and 19%, respectively. However, no clinically significant differences in the pharmacokinetics of valproic acid were observed when administered concomitantly with ORLYNVAH. AUC0-tau and Cmax decreased by 8.4% and 7%, respectively, with concomitant administration of ORLYNVAH.
In Vitro Studies
CYP450 Enzymes
Sulopenem does not inhibit CYP1A2, CYP2B6, CYP2C8, CYP2C9, CYP2C19, CYP2D6 or CYP3A or induce CYP1A2, CYP2B6, or CYP3A4/5.
Transporter Systems
Sulopenem is a substrate of OAT3 and does not inhibit BCRP, P-gp, BSEP, MATE1, MATE2K, OAT1, OAT3, OATP1B1, OATP1B3, OCT1, or OCT2. Probenecid is a substrate for BCRP and an inhibitor of OAT1/3, but does not inhibit BSEP, P-gp, or MRP2.
Microbiology
Mechanism Of Action
Sulopenem etzadroxil is a prodrug that is hydrolyzed to the active drug sulopenem after oral administration. Sulopenem has in vitro activity against gram-positive and gram-negative aerobic and anaerobic bacteria. The bactericidal activity of sulopenem results from the inhibition of cell wall synthesis and is mediated through sulopenem binding to penicillin binding proteins (PBPs). In Escherichia coli, sulopenem demonstrated binding affinity for PBPs in the following order: PBP2 > PBP1A > PBP1B > PBP4 > PBP3 > PBP5/6.
Resistance
Resistance to sulopenem is caused by certain extended spectrum beta-lactamases (ESBLs) including carbapenemases, alteration of PBPs, over expression of efflux pumps and loss of outer membrane porins. Sulopenem demonstrated activity against Enterobacterales in the presence of certain beta-lactamases and ESBLs, e.g., AmpC, CTX-M, TEM, SHV. Sulopenem resistant mutants were selected in vitro at a frequency of 1×10-8.
Interaction With Other Antimicrobials
In vitro studies with sulopenem did not demonstrate antagonism with any of the following antimicrobials: amoxicillin, aztreonam, ceftriaxone, doxycycline, gentamicin, levofloxacin, nitrofurantoin, vancomycin or trimethoprim-sulfamethoxazole. The clinical significance of these in vitro findings is unknown.
Antimicrobial Activity
Sulopenem has been shown to be active against most isolates of the following microorganisms, both in vitro and in clinical infections [see INDICATIONS]:
Gram-negative Bacteria
Escherichia coli
Klebsiella pneumoniae
Proteus mirabilis
The following in vitro data are available, but their clinical significance is unknown. At least 90 percent of the following bacteria exhibit an in vitro minimum inhibitory concentration (MIC) less than or equal to the susceptible breakpoint for sulopenem against isolates of similar genus or organism group. However, the efficacy of sulopenem in treating clinical infections caused by these bacteria has not been established in adequate and well-controlled clinical trials.
Gram-positive Bacteria
Staphylococcus saprophyticus
Streptococcus agalactiae
Gram-negative Bacteria
Citrobacter freundii
Citrobacter koseri
Enterobacter cloacae species Complex
Klebsiella aerogenes
Klebsiella oxytoca
Proteus vulgaris
Providencia alcalifaciens
Providencia stuartii
Susceptibility Testing
For specific information regarding susceptibility test interpretive criteria, and associated test methods and quality control standards recognized by FDA for this drug, please see https://www.fda.gov/STIC.
Animal Toxicology And/Or Pharmacology
In a toxicology study in monkeys, daily oral administration of sulopenem etzadroxil for 30 days was associated with reduced red blood cell counts and increased reticulocytes at doses of ≥ 400 mg/kg/day (approximately 6-times the clinical sulopenem exposure for the MRHD of sulopenem etzadroxil based on AUC comparison). In the same animals, positive Coomb’s assay results demonstrated positive reactions for polyspecific anti-human globulin and anti-IgG suggesting red cell loss may have been mediated by antibodies. Similar findings were also observed in toxicology studies with sulopenem administered intravenously to monkeys.
Clinical Studies
Uncomplicated Urinary Tract Infections
Trial 1
A total of 2222 adult women with uncomplicated urinary tract infections (uUTI) were randomized and 2214 received trial medications in a randomized, double-blind clinical trial (Trial 1) (NCT05584657) comparing oral ORLYNVAH (sulopenem etzadroxil 500 mg and probenecid 500 mg) twice daily for 5 days to oral amoxicillin/clavulanate 875 mg/125 mg twice daily for 5 days.
The microbiological modified intent-to-treat (micro-MITT) population, which included all patients who had at least one uropathogen isolated at baseline (≥105 CFU/mL) and received at least one dose of study drug, consisted of 990 patients; the median age was 51 years and median weight was 73.5 kg. Patients were enrolled only from the United States. Patients were Caucasian (79.7%), African American (17.0%) or of another race (3.3%).
Composite response (combined microbiological response and clinical cure rates) was determined by comparing the response rate of ORLYNVAH to amoxicillin/clavulanate at the TOC visit (12 days after randomization) in the micro-MITT population as well as in two sub-populations: a) micro-MITTS (micro-MITT population with baseline pathogens susceptible to amoxicillin/clavulanate, MIC ≤8/4 μg/mL) and b) micro-MITTR (micro-MITT population with baseline pathogens non-susceptible to amoxicillin/clavulanate, MIC ≥16/8 μg/mL). Clinical cure was defined as the resolution of patient-reported uUTI symptoms and no new uUTI symptoms. Microbiological response was defined as a reduction of all baseline uropathogens to less than 103 CFU/mL in the urine.
ORLYNVAH demonstrated efficacy in the micro-MITTS population. The micro-MITTR population was small (N=67) and had insufficient power to draw conclusions regarding efficacy (Table 4).
Table 4. Composite Response1 at the Test of Cure Visit in Patients with uUTI, Trial 1
| Study Population |
ORLYNVAHa
n/N (%) |
Amoxicillin/ clavulanateb
n/N (%) |
Treatment Difference (95% CI)c |
| micro-MITTSd Population |
| Composite response |
296/480 (61.7) |
243/442 (55.0) |
6.7 (0.3, 13.0) |
| Clinical cure |
371/480 (77.3) |
339/442 (76.7) |
0.6 (-4.8, 6.1) |
| Microbiological response |
361/480 (75.2) |
295/442 (66.7) |
8.5 (2.6, 14.3) |
| micro-MITTRe population |
| Composite response |
22/42 (52.4) |
17/25 (68.0) |
-15.6 (-37.5, 9.1) |
| Clinical cure |
26/42 (61.9) |
18/25 (72.0) |
-10.1 (-31.5, 14.0) |
| Microbiological response |
29/42 (69.0) |
20/25 (80.0) |
-11.0 (-30.7, 12.0) |
1 Combined Clinical and Microbiological Success;
a 500 mg/500 mg orally twice daily for 5 days;
b 875 mg/125 mg orally twice daily for 5 days;
c The 95% confidence interval (CI) was calculated using the unstratified Miettinen and Nurminen method;
d microbiological modified intent-to-treat population with baseline pathogens susceptible (MIC ≤8/4 µg/mL) to amoxicillin/clavulanate;
e microbiological modified intent-to-treat population with baseline pathogens nonsusceptible (MIC ≥16/8 µg/mL) to amoxicillin/clavulanate. |
Composite response rates by pathogen are presented in Table 5.
Table 5. Composite Response Rate at Test of Cure by Baseline Pathogen from Patients with uUTI, Trial 1
| Study Population |
ORLYNVAHa
n/N (%) |
Amoxicillin/ clavulanateb
n/N (%) |
| micro-MITTS Population |
| Escherichia coli |
251/400 (62.8) |
210/374 (56.1) |
| Klebsiella pneumoniae |
31/57 (54.4) |
22/50 (44.0) |
| Proteus mirabilis |
5/13 (38.5) |
6/13 (46.2) |
| micro-MITTR Population |
| Escherichia coli |
12/23 (52.2) |
9/12 (75.0) |
| Klebsiella pneumoniae |
0 |
0 |
| Proteus mirabilis |
0 |
0 |
a 500 mg/500 mg orally twice daily for 5 days;
b 875 mg /125 mg orally twice daily for 5 days |
Trial 2
A total of 1660 adult women with uUTI were randomized and received trial medications in a multinational randomized, double-blind clinical trial (Trial 2) (NCT03354598) comparing oral ORLYNVAH (sulopenem etzadroxil 500 mg and probenecid 500 mg) twice daily for 5 days to oral ciprofloxacin 250 mg twice daily for 3 days. The micro-MITT population, which included all patients who had at least one uropathogen isolated at baseline (≥105 CFU/mL), consisted of 1105 patients; the median age was 53 years; median weight in the randomized population was 70.4 kg. Patients were enrolled from the United States (55%) and Eastern Europe (45%). Patients were Caucasian (90%), African American (9%) or of other races (1%).
Composite response (combined microbiological response and clinical cure) was determined by comparing the response rate of ORLYNVAH to ciprofloxacin at the TOC visit (12 days after randomization) in two primary populations:
- micro-MITTS (micro-MITT population with baseline pathogens susceptible to ciprofloxacin, MIC ≤1 μg/mL) and
- micro-MITTR (micro-MITT population with baseline pathogens non-susceptible to ciprofloxacin, MIC ≥2 μg/mL). Clinical cure was defined as the resolution of patient-reported uUTI symptoms and no new uUTI symptoms. Microbiological response was defined as a reduction of all baseline uropathogens to less than 103 CFU/mL in the urine.
ORLYNVAH demonstrated efficacy in the micro-MITTR population but did not demonstrate efficacy in the micro- MITTS population (Table 6).
Table 6. Composite Response1 at the Test of Cure Visit in Patients with uUTI, Trial 2
| Study Population |
ORLYNVAHa
n/N (%) |
Ciprofloxacinb
n/N (%) |
Treatment Difference
(95% CI)c |
P valued |
| micro-MITTRe Population |
| Composite response |
78/162
(48.1) |
49/149
(32.9) |
15.3
(4.3, 25.8) |
0.006 |
| Clinical cure |
136/162
(84.0) |
96/149
(64.4) |
19.5
(10.0, 29.0) |
|
| Microbiological response |
92/162
(56.8) |
66/149
(44.3) |
12.5
(1.4, 23.3) |
|
| micro-MITTSf Population |
| Composite response |
227/376
(60.4) |
300/418
(71.8) |
-11.4
(-17.9, -4.8) |
|
| Clinical cure |
305/376
(81.1) |
351/418
(84.0) |
-2.9
(-8.2, 2.4) |
|
| Microbiological response |
262/376
(69.7) |
336/418
(80.4) |
-10.7
(-16.7, -4.7) |
|
1 Combined Clinical Cure and Microbiological Response;
a 500 mg/500 mg orally twice daily for 5 days;
b 250 mg PO twice daily for 3 days;
c The 95% confidence interval (CI) was calculated using the unstratified Miettinen and Nurminen method;
d The P value was calculated using Cochran– Mantel–Haenszel test;
e microbiological modified intent-to-treat population with baseline pathogens susceptible (MIC ≤1 µg/mL) to ciprofloxacin;
f microbiological modified intent-to-treat population with baseline pathogens nonsusceptible (MIC ≥2 µg/mL) to ciprofloxacin |
Composite response rates by pathogen are presented in Table 7.
Table 7. Composite Response Rate at Test of Cure by Baseline Pathogen from uUTI Trial 2
|
ORLYNVAHa
n/N (%) |
Ciprofloxacin b
n/N (%) |
| micro-MITTR Population |
| Escherichia coli |
63/141 (44.7) |
41/131 (31.3) |
| Klebsiella pneumoniae |
9/15 (60.0) |
7/14 (50.0) |
| Proteus mirabilis |
8/9 (88.9) |
3/6 (50.0) |
| micro-MITTS Population |
| Escherichia coli |
187/316 (59.2) |
244/348 (70.1) |
| Klebsiella pneumoniae |
23/37 (62.2) |
24/35 (68.6) |
| Proteus mirabilis |
5/9 (55.6) |
10/11 (90.9) |
| a 500 mg/500 mg orally twice daily for 5 days; b 250 mg PO twice daily for 3 days |
Complicated Urinary Tract Infections - Lack Of Efficacy
ORLYNVAH is not indicated for the treatment of complicated urinary tract infections. Trial 3 (NCT03357614) was a phase 3, multi-center, double-blind, randomized trial designed to compare the efficacy, tolerability, and safety of IV sulopenem followed by oral sulopenem etzadroxil and probenecid with that of IV ertapenem followed by oral ciprofloxacin or amoxicillin/clavulanate for the treatment of complicated urinary tract infections (cUTI). Trial 3 did not demonstrate the efficacy of sulopenem IV followed by oral sulopenem etzadroxil and probenecid for the primary endpoint of composite response (combined clinical and microbiologic response) in the microbiologic modified intentto- treat (micro-MITT) population at the test-of-cure visit on Day 21 [see INDICATIONS].
Complicated Intra-Abdominal Infections - Lack Of Efficacy
ORLYNVAH is not indicated for the treatment of complicated intra-abdominal infections. Trial 4 (NCT03358576) was a phase 3, multi-center, double-blind, randomized trial designed to compare the efficacy, tolerability, and safety of IV sulopenem followed by oral sulopenem etzadroxil and probenecid with that of IV ertapenem followed by oral ciprofloxacin and metronidazole or amoxicillin/clavulanate for the treatment of complicated intra-abdominal infections (cIAI). Trial 4 did not demonstrate the efficacy of IV sulopenem followed by oral sulopenem etzadroxil and probenecid for the primary endpoint of clinical response in the micro-MITT at the test-of-cure visit on Day 28 [see INDICATIONS].