Ticarcillin: a review of its pharmacological properties and therapeutic efficacy

Overcoming Beta-Lactamase-Based Antimicrobial Resistance by Nanocarrier-Loaded Clavulanic Acid and Antibiotic Cotreatments

Antimicrobial resistance (AMR) is one of the major threats to modern healthcare. Many types of bacteria have developed resistance to multiple antibiotic treatments, while additional antibiotics have not been recently brought to market. One approach to counter AMR based on the beta-lactamase enzyme has been to use cotreatments of an antibiotic and an inhibitor, to enhance the antibiotic action. Here, we aimed to enhance this technique by developing nanocarriers of two cationic beta-lactam class antibiotics, amoxicillin, and ticarcillin, combined with a beta-lactamase inhibitor, clavulanic acid, which can potentially overcome this type of AMR. We demonstrate for the first time that beta-lactamase inhibitor-loaded nanocarriers in cotreatments with either free or nanocarrier-loaded beta-lactam antibiotics can enhance their effectiveness further than when used alone. We use surface-functionalized shellac-/Poloxamer 407-stabilized antibiotic nanocarriers on Pseudomonas aeruginosa, which is susceptible to ticarcillin but is resistant to amoxicillin. We show an amplification of the antibiotic effect of amoxicillin and ticarcillin loaded in shellac nanoparticles, both alone and as a cotreatment with free or nanocarrier-loaded clavulanic acid. We also report a significant increase in the antimicrobial effects of clavulanic acid loaded in such nanocarriers as a cotreatment. We explain the increased antimicrobial activity of the cationically functionalized antibiotic-loaded nanoparticles with electrostatic attraction to the bacterial cell wall, which delivers higher local antibiotic and inhibitor concentrations. The effect is due to the accumulation of the clavulanic acid-loaded nanocarriers on the bacterial cell walls that allows a higher proportion of the inhibitor to engage with the produced intracellular beta-lactamases. These nanocarriers were also found to have a very low cytotoxic effect against human keratinocytes, which shows great potential for overcoming enzyme-based AMR.

Discovery and Development of Antibacterial Agents: Fortuitous and Designed

Today, antibacterial drug resistance has turned into a significant public health issue. Repeated intake, suboptimal and/or unnecessary use of antibiotics, and, additionally, the transfer of resistance genes are the critical elements that make microorganisms resistant to conventional antibiotics. A substantial number of antibacterials that were successfully utilized earlier for prophylaxis and therapeutic purposes have been rendered inadequate due to this phenomenon. Therefore, the exploration of new molecules has become a continuous endeavour. Many such molecules are at various stages of investigation. A surprisingly high number of new molecules are currently in the stage of phase 3 clinical trials. A few new agents have been commercialized in the last decade. These include solithromycin, plazomicin, lefamulin, omadacycline, eravacycline, delafloxacin, zabofloxacin, finafloxacin, nemonoxacin, gepotidacin, zoliflodacin, cefiderocol, BAL30072, avycaz, zerbaxa, vabomere, relebactam, tedizolid, cadazolid, sutezolid, triclosan and afabiacin. This article aims to review the investigational and recently approved antibacterials with a focus on their structure, mechanisms of action/resistance, and spectrum of activity. Delving deep, their success or otherwise in various phases of clinical trials is also discussed while attributing the same to various causal factors.

Complicated Intra-Abdominal Infections: The Old Antimicrobials and the New Players

Complicated intra-abdominal infections (cIAIs) are an important cause of morbidity and mortality worldwide. They are diagnosed when the initial abdominal organ infection has spread into the peritoneal space. Successful treatment relies on adequate source control and appropriate empiric antimicrobial therapy. Inappropriate antimicrobial therapy may result in poor patient outcomes and increases in healthcare costs. Current guidelines recommend several single and combination antimicrobial regimens; however, empiric antimicrobial treatment has been complicated by the increasing rates of resistant organisms, especially the extended-spectrum β-lactamase (ESBL)-producing Enterobacteriaceae. Additionally, the overuse of carbapenems to combat these resistant pathogens has contributed to the rise of carbapenemase-producing microorganisms, especially Klebsiella pneumoniae. This increasing resistance has prompted the development of novel antimicrobials like ceftazidime-avibactam and ceftolozane-tazobactam, whose activity extends to ESBL-producing microorganisms. Furthermore, the optimal duration of antimicrobial therapy is still unknown, and further research is necessary to find a definitive answer. This review will focus on antimicrobial therapies recommended by the current guidelines, the individual properties of these agents, appropriate duration of therapy, recent clinical trials, and place in therapy of the antimicrobial agents recently approved for the treatment of cIAIs.

Pharmacokinetics of ticarcillin in the loggerhead sea turtle (Caretta caretta) after single intravenous and intramuscular injections

Three captive loggerhead sea turtles, Caretta caretta, were used in four trials, one i.v. and three i.m., to determine the pharmacokinetic properties of a single dose of ticarcillin. For the i.v. study, each turtle received a single 50 mg/kg dose and blood samples were collected at 0, 0.5, 1, 2, 4, 6, 8, and 12 hr and at 1, 1.5, 2, 2.5, 3, 4, 6, 8, 10, and 14 days after administration. For the i.m. study, each turtle received one of three dosages (25, 50, or 100 mg/kg) in a randomized complete block design and blood samples were collected at the same time intervals. Each trial was separated by a minimum of 28 days to allow for complete drug clearance. Drug concentration in plasma was determined by a validated liquid chromatography-mass spectrometry assay. For the i.v. study, the elimination half-life was 5.0 hr. The apparent volume of distribution and plasma clearance were 0.17 L/kg and 0.0218 L/hr/kg, respectively. For the i.m. study, mean time to maximum plasma concentrations ranged from 1.7 ( +/- 0.58) hr in the 50 mg/kg group to 3.7 (+/- 2.5) hr in the 100 mg/kg group. Mean bioavailability ranged from 45% ( +/- 15%) in the 50 mg/kg group to 58% (+/- 12%) in the 100 mg/kg group, and the mean residence time ranged from 7.5 ( +/- 2.6) hr in the 25 mg/kg group to 16 (+/- 6.8) hr in the 100 mg/kg group. Two turtles had slight alanine aminotransferase elevations that were not clinically apparent at two different dosages, but otherwise, blood chemistries were unaffected. Possible i.m. dosage regimens for loggerhead sea turtles are 50 mg/kg q24 hr or 100 mg/kg q48 hr. Liver enzymes should be monitored during treatment.

Serum levels and pharmacokinetics of ticarcillin and clavulanic acid in dog following parenteral administration of Timentin

The serum concentration-time data for ticarcillin (TICAR) and clavulanic acid (CLA) following intravenous and intramuscular administration of Timentin (TICAR, 50 mg/kg with CLA, 1.7 mg/kg) indicated that absorption of CLA following intramuscular injection and its overall elimination from the body was faster than that of TICAR. This is supported by comparison of certain pharmacokinetic parameters for TICAR and CLA. These include the shorter value of Tmax for CLA (11.45 +/- 1.60 min) than that for TICAR (29.93 +/- 1.94 min) and significant variation in the elimination rate constants (0.183 +/- 0.0018 min -1 for CLA vs. 0.0097 +/- 0.0006 min -1 for TICAR) for the intravenous group of animals. The biological half-life of CLA (approximately 39 min) was significantly shorter (P less than 0.01) than that of TICAR (approximately 73 min). In spite of initial faster absorption, the intramuscular bioavailability of CLA (65.02%) was less than that of TICAR (91.37%). Though the pharmacokinetic behaviour of TICAR and CLA is not similar, yet based on the therapeutically optimal concentrations of CLA and TICAR reached in serum, Timentin at the dose used in the present study should be effective in treating most TICAR-resistant Enterobacteriaceae infections in dogs. Timentin is not likely to be effective in the treatment of infections caused by TICAR-resistant pseudomonads, at the dose used in the present study.

In vitro susceptibility of Mycobacterium tuberculosis, Mycobacterium africanum, Mycobacterium bovis, Mycobacterium avium, Mycobacterium fortuitum, and Mycobacterium chelonae to ticarcillin in combination with clavulanic acid

The in vitro susceptibility of Mycobacterium tuberculosis, Mycobacterium bovis, Mycobacterium africanum, Mycobacterium avium, Mycobacterium fortuitum, and Mycobacterium chelonae (M. chelonei) to ticarcillin in combination with calvulanic acid (CA) was studied by the agar dilution method. All the M. tuberculosis, M. bovis, and M. africanum strains were inhibited at a ticarcillin concentration of 32 micrograms/ml or lower in combination with 5 micrograms of CA. M. chelonae and M. avium strains proved resistant to more than 128 micrograms of ticarcillin plus 5 micrograms of CA per ml. M. fortuitum strains needed 128 micrograms of ticarcillin plus 5 micrograms of CA to inhibit approximately 30% of the isolates.

Timentin therapy for bone, joint, and deep soft tissue infections in children

Timentin, a combination of clavulanic acid (0.1 g) and ticarcillin (3.0 g), has proved effective in vitro against bacterial pathogens that produce beta-lactamases. The usual etiologic bacteria of osteochondritis of the foot (Pseudomonas species) and osteomyelitis/septic arthritis (Staphylococcus aureus) are commonly resistant to penicillins. To date, we have used Timentin to treat 30 children with bone, joint, and deep soft tissue infections. Timentin was administered intravenously at an average dosage of 207 mg/kg per day for mild to moderate infection and 310 mg/kg per day for bone and joint infections with systemic signs (sepsis). The lower dose was used in 24 patients and the other six patients, who had signs of sepsis, received the higher dose. All patients received Timentin intravenously over 30 minutes every four to six hours for a minimum of five days (mean 6.6 +/- 2.6 days, range five to 14 days). The mean time to defervescence and/or reduction in clinical symptoms was 1.6 +/- 1.3 days (range zero to four days). Osteochondritis due to P. aeruginosa was diagnosed in six patients, and septic bursitis, osteomyelitis, or septic arthritis due to S. aureus (13 patients) or Staphylococcus species and group A streptococci (four patients) was diagnosed in 17 patients. All isolates were susceptible to Timentin in vitro by disk-diffusion analysis. All patients showed a response to therapy with Timentin, with or without surgical intervention. All patients had clinical and microbiologic cures; no adverse reactions or side effects were observed. There have been no clinical or microbiologic relapses to date. Timentin may prove to be useful in specific bone and joint infections in children.

Displacement of bilirubin from cord serum by sulphadimethoxine, amoxycillin, clavulanic acid in combination with either amoxycillin or ticarcillin, temocillin and cloxacillin

The displacement of bilirubin from its binding sites in cord serum by sulphadimethoxine and various penicillins was studied using Sephadex gel filtration. Sulphadimethoxine displaced bilirubin at concentrations well within the normal therapeutic range of sulphonamide concentrations. Amoxycillin, clavulanic acid in combination with either amoxycillin or ticarcillin, temocillin and cloxacillin displaced bilirubin at concentrations much higher than those found clinically. It was concluded that the primary binding site/s of sulphadimethoxine and the secondary binding site/s of the penicillins were at or near the primary bilirubin binding site.

Susceptibility of gram-negative bacteria and Staphylococcus aureus to combinations of ticarcillin and clavulanic acid

Four hundred and fifty-nine blood culture isolates were tested for susceptibility to ticarcillin alone and ticarcillin plus clavulanic acid, a potent beta-lactamase inhibitor. The susceptibilities of the Staphylococcus aureus strains to cloxacillin, methicillin, vancomycin, rifampicin, cefoperazone, ceftriaxone and moxalactam and of the gram-negative strains to Augmentin, azlocillin, mezlocillin, piperacillin, cefoperazone, ceftriaxone, cefotaxime, cefsulodin and tobramycin were also measured. Seventy-one percent of staphylococcal strains were beta-lactamase positive. In the presence of clavulanic acid the ticarcillin spectrum was extended to include beta-lactamase producing Staphylococcus aureus, Serratia marcescens and Klebsiella. All the ticarcillin-resistant Enterobacteriaceae were rendered ticarcillin-sensitive by clavulanic acid. The anti-Pseudomonas activity of ticarcillin plus clavulanic acid differed little from that of azlocillin and piperacillin and was comparable to that of the third generation cephalosporins. The combination of ticarcillin with clavulanic acid should be tested in the treatment of patients with infections caused by ticarcillin-sensitive and ticarcillin-resistant bacteria.

Piperacillin sodium: antibacterial spectrum, pharmacokinetics, clinical efficacy, and adverse reactions

Piperacillin sodium is a beta lactam antibiotic with a broad range of antibacterial activity that includes gram-negative bacilli, gram-positive cocci (except penicillinase-producing S. aureus) and anaerobic pathogens such as Clostridium difficile, and Bacteroides fragilis. Piperacillin inhibits many of the members of the Enterobacteriaceae, including Klebsiella sp and Pseudomonas, at lower concentrations than required for carbenicillin and ticarcillin. Piperacillin sodium is administered by intramuscular and intravenous injection and is widely distributed throughout body fluids and tissues. Like other newer penicillins, piperacillin is excreted by both renal and biliary mechanisms. The primary route of elimination is by glomerular filtration, which results in high urinary concentrations of the unchanged compound. Piperacillin has been approved for patients with serious infection caused by susceptible strains of specific organisms in intra-abdominal, urinary tract, gynecologic, lower respiratory tract, skin and skin structure, bone and joint, and gonococcal infections and septicemia. As with other penicillins, piperacillin has a low frequency of toxicity. The usual dose of piperacillin in adults with serious infections with normal renal function is 3-4 g every 4-6 hr as a 20-30 min infusion, with a maximum dose of 24 g per day. It is stable in most large volume parenteral solutions. Less serious infectins (requiring smaller dosages) may be treated by intramuscular injection; however, no more than 2 g should be given at any one injection site. Overall, piperacillin has a greater degree of activity than other penicillins. Evidence from prospective studies indicates that piperacillin is a highly effective agent for the treatment of patients with infections caused by susceptible organisms.