Antibacterial Activities of SM-1652 Compared with Those of Other Broad-Spectrum Cephalosporins

Transcription

1 ANTIMICROBIAL AGENTS AND CHEMOTHERAPY, Nov. 1982, P /82/ $02.00/0 Copyright 1982, American Society for Microbiology Vol. 22, No. 5 Antibacterial Activities of Compared with Those of Other Broad-Spectrum Cephalosporins MASUHIRO KATO,'* MATSUHISA INOUE,2 AND SUSUMU MITSUHASHI1i2 Department of Microbiology' and Laboratory of Drug Resistance in Bacteria,2 School of Medicine, Gunma University, Maebashi, Japan Received 12 April 1982/Accepted August 1982 The in vitro and in vivo activities of were compared with those of other cephalosporins. possessed a wide antibacterial spectrum which included activity against Pseudomonas aeruginosa. It also exhibited potent antibacterial activities against gram-positive cocci and clinical isolates of glucose nonfermentative bacteria. Most notably, its activity against glucose nonfermentative bacteria was the highest of all of the drugs tested. The bactericidal activity of was compared with that of cefoperazone. The difference between the minimum bactericidal concentration and the minimum inhibitory concentration of was actually smaller than that of cefoperazone for Escherichia coli and clinical isolates of indole-positive Proteus spp. was stable for most s but was hydrolyzed to some extent by penicillinases. The in vivo therapeutic effect of against infections in mice was better than those of cefazolin and cefoxitin. The in vivo antipseudomonal activity of was second to that of cefsulodin. Komatsu et al. (2) first reported on the structure and antibacterial activities of (Fig. 1), a new semisynthetic cephalosporin. According to the report of these authors, was as active as cefazolin against gram-positive cocci and somewhat superior to cefazolin in potency and breadth of activity against gram-negative rods, and its antipseudomonal activity was comparable to that of cefsulodin. Matsui et al. (4) and Koyama et al. (M. Koyama, N. Nakatsuru, K. Yoshinaga, H. Matsui, C. Ikeda, K. Yano, and T. Noguchi, Program Abstr. Intersci. Conf. Antimicrob. Agents Chemother. 20th, New Orleans, La., abstr. no. 149, 1982) examined the pharmacokinetics of in animals and humans and showed that this agent gives rise to high and persistent blood levels. Our report is concerned with the comparative in vitro activities of and those of other new cephalosporins against various gram-positive cocci, Enterobacteriaceae, and some glucose nonfermentative bacteria. In addition, we report on the bactericidal activity of, its susceptibility to P-lactamases, and its efficacy against diverse experimental infections in mice. MATERIALS AND METHODS Drugs. (Sumitomo Chemical Co., Ltd.), cefoperazone (Toyama Chemical Co., Ltd.), cefsulodin and cefmenoxime (Takeda Industries Ltd.), cefotaxime (Hoechst Japan Ltd.), cefmetazole (Sankyo Co., Ltd.), cefoxitin (Daiichi Seiyaku Co., Ltd.), and moxalactam (Shionogi & Co., Ltd.) were gifts from manufacturers. Other antibiotics were acquired from commercial sources. Media. Media used in this study included heart infusion agar (Nissui Pharmaceutical Co., Ltd.), brain heart infusion agar and broth (Nissui), antibiotic medium 3 (Difco Laboratories) and peptone water (10 g of polypeptone and 5 g of NaCl in 1,000 ml of purified water). Organisms. Standard strains for assaying antibacterial activity were stored in the Laboratory of Drug Resistance in Bacteria in Gunma University, Gunma, Japan, by the Japan Society of Chemotherapy and were maintained in gelatin disks under desiccated conditions. Clinical isolates, 1,581 of which were used for the determination of minimum inhibitory concentrations (MICs), were stored in cooked-meat medium or frozen skim milk, purified from the stock media on an appropriate agar plate, and then used for preincubation. Minimum bactericidal concentrations (MBCs) were determined for isolates each of Escherichia coli, Klebsiella pneumoniae, indole-positive Proteus spp., and Pseudomonas aeruginosa selected at random from isolates used for MIC determinations. OH (AJ.CONHCHCONH FIG. 1. Chemical structure of. 721

2 722 KATO, INOUE, AND MITSUHASHI TABLE 1. Antibacterial spectra of and other cephalosporins MIC (Rg/ml) ofa: Strain CFS CMZ Staphylococcus aureus FDA 209P JC S. aureus Terajima 0.10 S. aureus MS Streptococcus pyogenes Cook ' Bacillus subtilis ATCC Micrococcus luteus ATCC Escherichia coli NIHJ JC E. coli K-12 C Klebsiella pneumoniae PCI _0.013 '0.013 Salmonella typhimurium IID S. typhi 901 _0.013 S. paratyphi '0.013 S. shottmuelleri 8006 '0.013 S. entertidis G Serratia marcescens IAM Proteus morganii IF '0.013 _0.013 P. vulgaris OX-19 _0.013 '0.013 P. vulgaris HX-19 '0.013 '0.013 ' P. rettgeri IF '0.013 P. mirabilis IF Enterobacter aerogenes ATCC E. cloacae Pseudomonas aeruginosa IF03445 P. aeruginosa NCTC P. aeruginosa PA01 a, Cefoperazone;, cefotaxime;, cefazolin; CFS, cefsulodin; CMZ, cefmetazole. TABLE 2. Comparative in vitro activities of and other cephalosporins against clinical isolates of 19 species Strain (no. of species tested) Antibiotica Range %o 90%/o Staphylococcus aureus () - S. epidermidis (53) Streptococcus pyogenes (92) Escherichia coli (200) Klebsiella pneumoniae (200) Proteus mirabilis () = ' ' '= '0.013-> '= '= ANTIMICROB. AGENTS CHEMOTHER. _0.013 <0.20 '

3 VOL. 22, 1982 ANTIBACTERIAL ACTIVITIES OF 723 Strain (no. of species tested) Proteus vulgaris () P. morganii () P. rettgeri (35) P. inconstans (32) Enterobacter cloacae (110) E. aerogenes (24) Citrobacterfreundii (26) Serratia marcescens (205) Haemophilus influenzae () Pseudomonas aeruginosa (200) TABLE 2-Continued Antibiotica MIC (p.g/ml) % '-0.20 ' T% '-0.20 MXA CMX CFS P. maltophilia (34) P. cepacia (55) Acinetobacter spp. () = a, Cefoperazone;, cefotaxime;, cefazolin; MXA, moxalactam; CMX, cefmenoxime; CFS, cefsulodin. Range - - ' C0.20- C = = =0.20- = '=0.20- ' =0.20- = '=

4 724 KATO, INOUE, AND MITSUHASHI oo r-400 In vitro antibacterial activity. MICs were determined by the agar dilution method on heart infusion agar plates containing serial twofold dilutions of a drug. X E. The isolates were grown at 37 C for 18 h in peptone u Z Z Z - water. Brain heart infusion broth and agar were used for culturing Streptococcus pyogenes. Brain heart infusion broth and agar supplemented with 10,ug hemin (Sigma Chemical Co.) and 2 Fig of NAD (Sigma) of per ml were used for culturing Haemophilus influenzae. Precultured isolates in the appropriate broth were diluted 1: in fresh broth and inoculated with an A A A inoculum-replicating apparatus (Microplanter, Sa- v 0 e4nrm n kuma Seisakusho Ltd.) which delivered about 5-,Jl m0 c VV ll spots of broth, yielding a final inocula of i05 to N colony-forming units. MICs were scored after 18 h of so... incubation at 37 C. CZ., - *Inthe > broth dilution method, 0.1 ml of bacterial suspension in antibiotic medium 3 was inoculated into 0.4 ml of antibiotic medium 3 containing serial twofold dilutions of a drug, yielding a final inoculum of i05 CL i4 >A A A > colony-forming units per ml. After 18 h of incubation ac soxz S at 37 C, MICs were scored as the lowest concentrations of drugs that inhibited the visible growth of bacteria. Determination of MBCs. After MICs were determined by the broth dilution method, one loopful (about - c 5,ul) of culture that showed no visible growth was inoculated onto antibiotic-free heart infusion agar *oqn plates. After 18 h of incubation at 37 C, MBCs were go v: lscored as the lowest concentrations drugs which pre- U ra V zz z vented colony formation of bacteria on the plate. I-, StabilIty against P-lactamases. The P-lactamases X0 E I were purified in our laboratory (5) and stored at -70 C. Hydrolysis of,b-lactam antibiotics was aso sayed by the methods of O'Callaghan et al. (7), Waley 8z ~ 8 8(9), and Minami et al. (5). The hydrolysis of was measured at 275 nm. Substrate specificity was o # AN Al expressed as the relative rate of hydrolysis of the antibiotics, taking the absolute rate of penicillin G or o o ocephaloridine i hydrolysis as. X VII > Animln experiments. Male ICR mice weighing 20 ± 1 g each were used in groups of 10 animals per organism per dose of 1-lactam antibiotic. Challenging organisms EcJ ; IRt w were suspended in saline or 5% mucin. A 0.5-ml SE suspension of the organism to be tested was injected intraperitoneally. The test antibiotics were administered by subcutaneous infection at 1 and 4 h after the S > A A > bacterial challenge. The mice were observed daily for o -o, Js e., 4 days. In this test, all of the untreated mice died 2 O O e O > *c within 2 days. The therapeutic effect of the test P- - _- lactam antibiotics was calculated by the Litchfield- ; Ci o'i > 3Wilcoxon method and expressed as the % effective dose in milligrams per kilogram of body weight. vl,*(>results The antimicrobial activities of and,..c 0 other cephalosporins are shown in Table 1. SM displayed a broad antibacterial spectrum which included activity against P. aeruginosa. az.c 0. u The activities of both cefotaxime and cefopera- <-qge3 ^zone against Enterobacteriaceae were signifi- *,243 S t cantly higher than that of. The latter.00 Q Z U ANTIMICROB. AGENTS CHEMOTHER. < compound was somewhat more active than cefoperazone and cefotaxime against P. aeruginosa. The spectra and levels of activity of cefazolin,

5 VOL. 22, 1982 ANTIBACTERIAL ACTIVITIES OF 7 TABLE 4. Stabilities of and other P-lactams to various P-lactamases Substrate profile (relative V,,x)a CER CFX PC-G Escherichia coli GN5482 Chromosomally mediated < <1 <1 63 Enterobacter cloacae Chromosomally mediated <1 1 <1 <1 12 GN7471 Citrobacterfreundii Chromosomally mediated < <1 <1 3 GN7391 Serratia marcescens Chromosomally mediated <1 <1 3 GN10857 Proteus rettgeri GN4430 Chromosomally mediated <1 99 <1 <1 <1 3 P. morganii GN5407 Chromosomally mediated <1 20 <1 <1 <1 16 Pseudomonas aeruginosa Chromosomally mediated < <1 <1 29 GN10362 Proteus vulgaris Cefuroxime hydrolyzing <1 20 GN7919 enzyme Pseudomonas cepacia Cefuroxime hydrolyzing <1 161 GN11164 enzyme Bacteroides fragilis Cefuroxime hydrolyzing <1 60 GN11478 enzyme Escherichia coli W3630/ Penicillinase type I <1 <1 Rms 212 (TEM-I) E. coli W3630/Rms 213 Penicillinase type II <1 <1 (OXA-1) E. coli W3630/Rte 16 Penicillinase type III <1 <1 (OXA-2) Pseudomonas aeruginosa Penicillinase type IV <1 <1 M1/Rms 139 (PSE-3) a CER, Cephaloridine; CFX, cefoxitin;, cefazolin;, cefoperazone;, cefotaxime; PC-G, penicillin G. cefmetazole (6), and cefsulodin (8) were similar to those reported elsewhere. The activities of, cefoperazone, cefotaxime, and cefazolin or cefsulodin against various clinical isolates are shown in Table 2. These agents exhibited similar activities against gram-positive cocci with minor exceptions. exhibited a broad spectrum but moderate levels of activity for all strains of Enterobacteriaceae tested. Cefotaxime exhibited the highest antibacterial activity against Enterobacteriaceae of all of the drugs tested, followed by cefoperazone. In contrast, exhibited the highest activity against glucose nonfermentative bacteria, being comparable to cefsulodin and 2 to 16 times more active than other cephems. The mean MICs and MBCs of were higher than those of cefoperazone, except for P. aeruginosa isolates, for which the mean MICs and MBCs of were second to cefsulodin (Table 3). On the other hand, the percentage of isolates which showed a MBC/MIC ratio of less than 2 for drugs against E. coli, K. pneumoniae, indole-positive Proteus spp., and P. aeruginosa, respectively, were as follows:, 80, 44, 82, and 80%; cefoperazone, 72, 42, 60, and 88%; and cefsulodin against P. aeruginosa, %. was not hydrolyzed by the common chromosomal s, except for that of Serratia marcescens, but was hydrolyzed to some extent by the p-lactamases of Proteus vulgaris, Pseudomonas cepacia, and Bacteroides fragilis (Table 4). These enzymes are distinguishable from other chromosomal s because of their ability to hydrolyze the cefuroxime group, their smaller molecular weights, and their susceptibility to clavulanic acid and CP They are classified as cefuroxime-hydrolyzing enzymes (cefuroximase) (1). was hydrolyzed to some extent by penicillinase type I (TEM I), type II (OXA I), and type IV (PSE III). Almost the same pattern of hydrolysis was observed for cefoperazone, although the hydrolyzed percentages were smaller as compared with those of. Cefoxitin was not hydrolyzed by any,-lactamase, and cefotaxime was hydrolyzed by the cefuroximase. The protective effects of and other cephalosporins against infections in mice are

6 726 KATO, INOUE, AND MITSUHASHI TABLE 5. Protective effects of and other,-lactams against infections in mice Stri (CFU) Challenge LD Antibiotic per mousea (MIC [pg/nm])b ED5 (mg/kg)c Escherichia coli ML4707 (2.5 x 106) () 7.30 ( ) () 4.10 ( ) () 1.65 ( ) CZX () 1.13 (-1.64) CFX () 37.0 ( ) () 34.0 ( ) Klebsiella pneumoniae 5 (7.3 x 106) () 4.60 ( ) GN6445 (0.10) 0.88 ( ) () 0.36 ( ) CZX () 0.34 ( ) CFX () 62.5 ( ) () 6.10 ( ) Pseudomonas aeruginosa 15 (1.2 x 105) () 31.0 ( ) GN3315 With 5% mucin CFS () 17.0 ( ) () ( ) (ND) >200 CZX (ND) >200 CBPC (ND) >200 a Male ICR mice weighing 19.0 to 21.0 g each were injected intraperitoneally and given the indicated number of %o lethal doses (LD) of antibiotic 1 and 4 h later. CFU, Colony-forming units. b, Cefoperazone;, cefotaxime; CZX, ceftizoxime; CFX, cefoxitin;, cefazolin; CBPC, carbenicillin; ND, not determined. c Numbers in parentheses are 95% confidence limits. ED, %o Effective dose. shown in Table 5. The protective activity of SM against experimental infection with E. coli ML1410 was lower than those of ceftizoxime and cefotaxime, comparable to that of cefoperazone, and superior to those of cefoxitin and cefazolin. The protective activity of against infection with K. pneumoniae GN6445 was comparable to that of cefazolin and lower than those of ceftizoxime, cefotaxime, and cefoperazone. Against Pseudomonas aeruginosa GN3315 infection, was slightly less active than cefsulodin but three times as active as cefoperazone. Cefotaxime, ceftizoxime, and carbenicillin were not effective against such infection. DISCUSSION In this report, we have elaborated on the broad antibacterial spectrum, high antipseudomonal activity, and high bactericidal activity of. Its activities against various experimental infections in mice were lower than those of third-generation cephems, with the exception of P. aeruginosa infection. It has a half-life in humans (1-g bolus injection) of about 4 to 5 h and gives rise to a plasma concentration of 8,ug/ml for at least 24 h. This high plasma concentration may be enough to inhibit bacterial growth, although displayed only moderate activity against Enterobacteriaceae. Our experiment ANTIMICROB. AGENTS CHEMOTHER. with animals was not enough to determine whether the synergistic effect of the features mentioned above is seen or not. For this purpose, some other animal experiment system, in which the pharmacokinetics of are more similar to those seen in humans, such as pouch infection with rabbits, will have to be undertaken. LITERATURE CITED 1. Hirai, K., K. Sato, N. Matsubara, R. Katsumata, M. Inoue, and S. M ital Immunological properties of betalactamases that hydrolyze cefuroxime and cefotaxime. Antimicrob. Agents Chemother. 20: Komatsu, T., T. Okuda, H. Noguchl, M. FWbusawa, K. Yaio, M. Kato, and S. Mtuh , a new parenterally active cephalosporin: microbial studies. Curr. Chemother. Infect. Dis. 1: Matsubara, N., S. MInamI, T. Muraoka, I. Salkawa, and S. Mltauhashl In vitro antibacterial activity of cefoperazone (T-1551), a new semisynthetic cephalosporin. Antimicrob. Agents Chemother. 16: Matsui, H., K. Yano, H. Nakatani, and K. Mashimo , a new parenterally active cephalosporin: pharmacological studies. Curr. Chemother. Infect. Dis. I: Minaml, S., M. Inoue, and S. Mltsuhashi Purification and properties of in Escherichia coli. Antimicrob. Agents Chemother. 18: Nakao, H., H. Yan wa, B. Shnlzu, M. Kaneko, M. Nagano, d S. Supwara A new semisynthetic 7amethoxy-cephalosporin, CS-1170: 70-[[(cyanomethyl) thio] acetamido] -7a - methoxy [[(1- methyl -1H - tetrazol -5 - yl) thio]methyl]-3-cephem-4-carboxylic acid. J. Antibiot. (Tokyo) 29:

7 VOL. 22, 1982 ANTIBACTERIAL ACTIVITIES OF O'Callaghan, C. H., P. W. Muggleton, and G. W. Ross Effects of I-lactamase from gram-negative organisms on cephalosporins and penicillins, p Antimicrob. Agents Chemother Tsuchlya, K., M. Kondo, and H. Nagatomo SCE-129, anti-pseudomonal cephalosporin: in vitro and in vivo antibacterial activities. Antimicrob. Agents Chemother. 13: Waley, S. G A spectrophotometric assay of p- lactamase action on penicillins. Biochem. J. 139: