Double-blind randomised controlled trial of monoclonal antibody to human tumour necrosis factor in treatment of septic shock

I Articles I Double-blind randomised controlled trial of monoclonal antibody to human tumour necrosis factor in treatment of septic shock Edward A braharn, Antonio A nzueto, Guillerrno Gutierrez, Sidney Tessler, Gerry San Pedro, Richard Wunderink, Anthony Dal Nogare, Stanley Nasraway, Steve Berman, Robert Cooney, Howard Levy, Robert Baughrnan, Mark Rurnbak, R Bruce Light, Lona Poole, Randy Allred, John Constant, James Pennington, Steven Porter, for the NORASEPT I1 Study Group*

Summary Background Despite the availability of potent antibiotics and intensive care, mortality rates from septic shock are 40-70%. We assessed the safety and efficacy of murine monoclonal antibody to human tumour necrosis factor a (TNFa MAb) in the treatment of septic shock. Methods In

a randomised, multicentre, double-blind, placebo-controlled clinical trial in 105 hospitals in the USA and Canada, we randomly assigned 1879 patients a single infusion of 7.5 mg/kg TNFa MAb (n=949) or placebo (0.25% human serum albumin n=930). Our main outcome measurement was the rate of all-cause mortality at 28 days. Findings 382 (40.3%)of 948 patients who received TNFa MAb and 398 (42.8%) of 930 who received placebo had died at 28 days (95%CI -0.02 to 0.07, p=0.27). We found no association between therapy with TNFa MAb and

increased rapidity in reversal of initial shock or prevention

of subsequent shock. Similarly, baseline plasma interleukin6 concentrations of more than 1000 pg/mL or detectab!e circulating TNF concentrations were not associated with improvement in survival after TNFa MAb therapy. Coagulopathy but not other organ or system failures, was significantly decreased in the TNFa MAb group compared with placebo (day 7, p
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adverse events were reported in 55.2% of patients given placebo and 54.1% in the TNFa MAb group. Interpretation We did not find. an improvement in survival after septic shock with TNFa MAb. Therapy not solely dependent on T N F a blockade may be required to improve survival.

Lancet 1998;351: 929-33 See Commentary page 922

Introduction In the USA there are about 500 000 cases of sepsis due to gram-negative, gram-positive, and fungal organisms every year, and about half of these develop hypotension (shock) refractory to fluid resuscitati0n.l Septic shock is the most common cause of death in intensive-care units in the USA;’ mortality rates are estimated at 40-70%, despite the availability of potent antibiotics and intensive supportive care.%’ Therapies that can be used early, irrespective of the infecting organism or organisms, are of particular interest in the treatment of sepsis, since prediction of the infecting organisms can be difficult based on clinical presentation in critically ill septic-shock patient^.^ Blood cultures are positive in about 45% of patients with sepsis.’ In studies of sepsis, at least a third of all patients with positive cultures had gram-positive infections and about 40-50% had gramnegative infecti~ns.~J~ However, gram-positive organisms are predominant in patients with positive blood cultures.6 Although the pathophysiology of systemic inflammation and organ dysfunction is complex, tumour necrosis factor a (TNFa) seems to be a principal mediator that can cause the manifestations of sepsis and septic shock, including hypotension, activation of the clotting cascade, and organ or system dysfuncti~n.”-~~ Anti-TNFa antibodies protect. animals from death caused by endotoxins, gram-negative bacteria such as Escherichia coli, and gram-positive bacteria such as Staphylococcus au~eus.’~-~~ Two large clinical trial^^^'^ that used murine monoclonal antibodies to human TNFa (TNFa MAb) showed a decrease in mortality among patients with shock and organ dysfunction who were treated with TNFa MAb. We aimed, in a randomised, placebo-controlled, double-blind, clinical trial with a prospectively defined analytical plan, to further assess the efficacy and safety of T N F a MAb therapy in patients with septic shock.

Methods The protocol was approved and carried out in accordance with the guidelines of institutional review boards at each participating centre.

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Adults older than 18 years admitted to hospital with shock due to sepsis within 12 h before and present at the time of randomisation were eligible for enrolment. All the enrolment criteria had to be filled. The criteria were: clinical evidence of acute infection; hyperthermia (rectal, core, oral, or axillary temperature 238.3”C [101”F)) or hypothermia (rectal or core temperature <35.6”C [96”Fl); tachycardia (>90 beatsimin), tachypnea (>20 breathdmin) or need of mechanical ventilation; hypotension (systolic blood pressure <90 mm Hg for >30 min, a decrease in systolic blood pressure of >40 mm Hg from previously established values for >30 min, or vasopressor use to maintain systolic blood pressure >90 mm Hg) present at enrolment and refractory to an intravascular volume challenge of at least 500 mL; and onset of inadequate organ function or perfusion within 12 h before randomisation, as manifested by at least one of altered mental status (Glasgow coma score <14, or acute change from baseline in behaviour or cognitive function not due to sedatives, hypnotics, or localised central-nervous-system infection alone), hypoxaemia (PaO, <10 kPa on room air, or PaOJFiO, - 3 8 0 , appropriately adjusted for altitude, and not due only to localised pulmonary infection), raised plasma lactate or metabolic acidosis (pH <7.3 or base excess <-lo mmol/L), oliguria (hourly urine output <30 mL or <0.5 mUkg for at least 1 h, unresponsive to a 500 mL fluid challenge), or disseminated intravascular coagulation (defined as either drop in platelets >25% from the patient’s baseline or, without baseline value, a decrease of >25% from the lower end of the normal range, plus any one of >20% increase in prothrombin time, partial thromboplastin time, or fibrin split products from the patient’s baseline or upper limit of the normal range if no baseline value, or D-dimer M O O ng/rnL or above the upper limit of the normal range, or abnormal prothrombin time; or partial thromboplastin time plus either abnormal fibrin split products or D-dimer, as defined above). Patients were not eligible if they had been previously enrolled in a TNFa MAb study, if they did not give informed consent, or if they had underlying diseases other than sepsis severe enough that expected survival was less than 2 months after infusion. Patients were also excluded if they had received any investigational agent within 30 days of study-drug infusion, murine antibodies or products derived from mice, pentoxifylline within 48 h before study-drug infusion, prednisone 0.5 mg/kg or more daily or other glucocorticoid equivalent for more than 3 days (patients were not excluded for a single bolus of steroids); if they had a history of hypersensitivity reactions to human-albumin administration; were pregnant or lactating; immunosuppressed because of administration of cyclosporin, azathioprine, or chemotherapy; had granulocyte counts of less than 1OOOipL (except due to sepsis); had known hypersensitivity to mice; had uncontrolled haemorrhage that required multiple transfusions at the time of anticipated infusion of study drug; had more than 20% total bodysurface-area burns; or weighed more than 130 kg. Hybridomas producing TNFa MAb were obtained from fusions of myeloma cells with spleen cells from mice immunised with recombinant TNFa MAb. One MAb of the IgG, subclass with high ma-neutralising activity was selected for further development.21,22 Exposure to pH 4.0 was applied as a viralinactivation step during purification. In-vitro anti-TNFa activity was confirmed in each lot before use. The TNFa MAb lots used in this study were PR3222-PR3224 and PR37BOOl-PR37B006, TNFa MAb (7.5 mg/kg) and placebo were shipped to each centre in prerandomised blocks of eight kits, randomised by computers (Almedica drug labelling system, version 5.05a). Kits were provided as sterile lyophilised preparations containing glycine and maltose, masked for which treatment they contained. The preparations were reconstituted with 10 mL sterile water, which gave 0.027 mg glycine, 1% maltose, and either 20 mg/mL TNFa MAb or 2.5 mg/mL human albumin. We diluted appropriate volumes of reconstituted preparations to 100 mL with 5% aqueous dextrose solution, dependent on the weight of the patient. Patients with septic shock of 1 2 h or less duration were enrolled, defined by the onset of shock or of organ or system

930

1879 randomised I

7.5

mg/ kg

H-1

placebo

H1 -

g&

follow-up

follow-up

1excluded by institutional review board from efficacy analysis

all-cause 944 analysed mortality

all-cause 925 analysed mortality

Figure 1:Trial profile

dysfunction (not necessarily by the time of hospital admission). At enrolement we measured APACHE I1 score,2’ and made plasma interleukin-6 and TNFa blood cultures. Patients were randomly assigned 7.5 mgkg TNFa MAb or placebo (0.25% human serum albumin). Study drug had to be administered within 4 h of randomisation as a single 30 min (with 10 min leeway) intravenous infusion. Patients received standard supportive medical or surgical therapy (fluids, vasopressors, antibiotics, haemodynamic monitoring, and surgery) if needed during the 28 days after infusion. During this period, we measured efficacy and safety, including vital signs, arterial blood gases, physical examinations, routine haematological and chemistry tests, and blood and urine cultures (as appropriate). We determined the presence of serum antibodies to human anti-TNFa MAb (HAh4As) for all patients with a standard ELISA before and 28 days after infusion. A “preformed” HAMA concentration was defined as the ratio of three times the HAMA concentration before infusion in a given patient to that in a control. A “positive” HAMA titre was at least a four-fold increase in HAMA concentration compared with the preinfusion concentration (or compared with the lower limit of detection of the assay for patients with undetectable preinfusion concentrations). We measured plasma TNFa and interleukin-6 concentrations by ELISA (Cistron Biotechnology, Pine Brook, NY,USA for TNFa, and Bayer Corporation, Berkeley, CA for interleukin-6). We defined organ or system failure (adapted from Tran and colleagues2’) as: renal failure (serum creatinine >280 pmol/L or dialysidultrafiltration), adult respiratory distress syndrome (bilateral pulmonary infiltrates on chest radiograph plus PaO, <70 mm Hg with an FiO, of S0.4 or PaO,/FiO, <200), pulmonary failure in non-adult respiratory distress syndrome (respiratory rate <5 breathsimin or >50 breathsimin, mechanical ventilation for >3 days, or FiO, >0.4 or peak end-expiratory pressure >5 cm water, or both), hepatic failure (total bilirubin >51 pmolk in the absence of haemolysis and serum alanine aminotransferase more than twice normal, or hepatic encephalopathy), neurological failure (Glasgow coma scale <6 without sedation), and disseminated intravascular coagulation, as defined for inclusion criteria. Investigators classified organisms as causative or colonisers. We used causative bacteria isolated from a putative infection thought to have caused septic shock at enrolment to assess the

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Mean (SD) age (years) Mean (SD) weight (kg) Male/female Proportion white patients Mean (SD)APACHE II score Mean (SD)preinfusionshock duration I h\

TNFa MAb (n=949)

Placebo (n-930)

59.2(17.1) 74.3(19.4) 60.5% 65.3% 28.4(7.9) 8.3(4.8)

59.0(17.2) 73.9(19.0) 60.5% 64.4% 28.8(8.2) 8.3(4.0)

-p

0.796 0.610 0.991 0.131 0.343 0.998

Table 1:Comparison of characteristics at enrolment

appropriateness of antimicrobial therapy. If the patient received at least one antibiotic to which all bacterial isolates were susceptible, the treatment was taken as appropriate. We also identified patients in whom at least one bacterial isolate causing septic shock was resistant to all administered antimicrobials, and patients not classified by either of these two groupings, mainly those in whom antimicrobial susceptibility was not tested. A safety committee, comprised of three critical-care and two infectious-disease experts who were not associated with study enrolment, was responsible for assessment of the reported adverse events and deaths. The primary efficacy variable was the proportion of patients in each treatment group alive at day 28, compared by MantelHaenszel and x2 statistics. An external statistician not involved in enrolment did one interim analysis of comparative efficacy and safety on data obtained from preliminary information on the first 950 enrolled patients. We used the O’Brien-Fleming method to adjust for the interim analysis in calculations of the sigtllficance level for the primary efficacy analysis at the end of the study, which was 0.048 (two-tailed). We prospectively defined as secondary efficacy variables death at days 7 or 14, reversal of shock, improvement in organ failure, and occurrence of new organ failure, which we tested at the 0.05 sigdicance level by Mantel-Haenszel and x2 statistics. We compared time to death during the 28 days after infusion (allcause) by a logrank test. We drew Kaplan-Meier survival curves to show differences between groups. We tested comparability of treatment groups at baseline and tested safety data with two-way analysis of variance techniques for continuous variables, and Mantel-Haenszel and x2 statistics for categorical variables. We did separate Mantel-Haenszel tests for patients surviving at day 7 and those surviving at day 28. The primary variable used for sample-size calculations was the proportion of infused patients in each treatment group surviving at day 28. We calculated the sample size, based on the results of a previous study; by assuming a 46% mortality rate in the placebo group and an expected 17% decrease in mortality in the TNFa MAb group at day 28. With a predicted need for 950 patients in the treatment and placebo groups, the study had about 90% power at the 0.048 significance level (two-tailed) for detection of a significant decrease in mortality to 38%. We increased the total projected enrolment by 15% to account for variability across centres.

-

TNFa MAb (n=949)

Placebo ( ~ 9 3 0 ) p

11 (1.2%) 186 (196%) 323 (24.0%) 274 (28.9%) 125 (13.2%) 30 (3.2%)

7 (0.8%) 198 (21.3%) 295 (31.7%) 266 (286%) 124 (13.3%) 40 (4.3%)

0,531

366 (38.6%) 546 (57.5%) 614 (64.7%) 480 (50.6%) 298 (314%)

357 (384%) 550 (59.1%) 606 (65.2%) 486 (52.3%) 283 (30.4%)

0,998 0.361 0,795 0.479 0.635

Number of hypoperhurbns

0 1 2 3 4 5

-

Type of hypopetfusion

Altered mental status Hypoxaemia Metabolic acidosis Oliguria Coagulopathy

Table 2: Comparison of organ and system hy’poperfusionat enrolment

Sites of infection were also similar, with the respiratory tract beirig the most common (TNFa MAb 29.6%, placebo 29-8%), followed by blood (TNFa MAb 27.8%, placebo 26.8%), intra-abdominal (TNFa MAb 11.9%, placebo 11-3%), and urinary tract (TNFa MAb 11*6%,placebo 12.7%). The proportion of patients with documented gram-negative, gram-positive, and mixed gram-positive and gram-negative infections were similarly distributed in the two study groups (gramnegative. TNFa MAb 27.6%, placebo 28.9%; grampositive, TNFa MAb 25.8%, placebo 23.3%; mixed, TNFa MAb 9.7%, placebo 10.2%). The causative organisms at enrolment were also similarly distributed in the two groups (table 3). In 710 (744%) patients in the TNFa MAb group and 690 (74.2%) in the placebo group antimicrobial treatment was appropriate, and 136 (14.3%) and 143 (15.4%), respectively, had at least one isolate resistant to all antimicrobials given. There was a non-significant difference between groups in the number of patients who had died at 28 days (382 [40.3%] of 948 TNFa MAb vs 398 [42.8%] of 930 placebo; 5.8% decrease [95% CI 4 0 2 0 to 0.0701, ~ ~ 0 . 2 7figure ; 2). After adjustment for centre and nine risk factors (age, sex, race, APACHE I1 score, origin of sepsis, organ failure, type of primary infection, bacteraemia or fungaemia, and duration of shock before infusion) in univariate and multivariate logistic regression the results remained similar. There was no significant effect of TNFa MAb therapy on time to death (p=0-31), 7-day all-cause mortality (-0,023 to 0.057, p=0.37), 14-day all-cause mortality (-0.021 to 0.065, p=0.31), reversal of septic shock at day 7 (p=0*22), resolution of baseline organ failure at day 7 (p=0.12 to p=0.70, dependent on organ failure), or

Results 1916 patients were enrolled and 1879 patients received treatment ( ~ 9 4 9 or ) placebo ( 1 ~ 9 3 0 )Ten . patients died and the investigator withdrew 27 before infusion (figure 1). At the time of infusion, 930 (98.0%) TNFa MAb and 905 (97.3%) placebo patients were in septic shock. Four (0.4%) TNFa MAb and five (03%) placebo patients were lost to follow-up by day 28 and their survival was unknown. In addition, the local institutional review board excluded one patient in the TNFa MAb group from the efficacy analysis because of no informed consent. Patients in the two groups had similar characteristics at enrolment (tables 1 and 2). In the TNFa MAb group, 73.8% of the infections were microbiologically documented, compared with 73.9% in the placebo group. The percentage of patients with bacteraemias in each group was similar (TNFa MAb 41.8%, placebo 41.1%).

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Organisms per treatment group

O m negatlve Total Escherichra colr Klebsiella/Cftrobacter spp Pseudomonas aeruginosa Enterobacter cloacae and spp Proteus mirabilis and spp Serratia marcescensand spp Other gram negative Gram posltlve Total Staphylococcusaureus Enterococcusspp Staphylococcusepidermidis Streptococcus pneumoniae Other eram oositive

.

TNFa MAb (n=1702)

Placebo (n=1673)

794 192 (24.2%) 148 (18.6%) 107 (13.5%) 84 (10.6%) 51 (6.4%) 41 (5.2%) 171 (21.5%)

815 206 (25.3%) 174 (21.3%) 136 (16.7%) 84 (10.3%) 51 (6.3%) 17 (2.1%) 147 (18.0%)

713 239 (33.5%) 121 (17.0%) 105 (14.7%) 94 (13.2%) 154 121.6%)

654 171 (26.1%) 115 (17.6%) 98 (15.0%) 91 (13.9%) 179 127.4%)

Table 3: Microbiology of infections at enrolment

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Organ or system hllura

T N k MAb (11-562)

Placebo (n-527)

Renal failure ARDS Non-ARDS pulmonary failure Hepatic failure Neurological failure Coagulopathy

47/500 (9.4%) 49/455 (10.8%) 101/238 (42.4%) 27/548 (4.9%) 12/517 (2.3%) 57/308 (18.5%)

36/465 (7.7%) 37/413 (9.0%) 96/238 (40.3%) 33/501(6.6%) 7/470 (1.5%) 80/292 (27.4%)

0.308 p

0.249 0.396 0.214 0.305

0,005

ARDS=adult respiratory distress syndrome.

Table 4: Frequency of subsequent allcause organ failure in day-28 survlvors

development of subsequent shock at day 7 (pz0.69). Results were also non-significant among patients surviving to day 28. There was a significant decrease in the frequency of new coagulopathy among survivors at day 7 and day 28 treated with T N F a MAb (day 7,73 [20.3%] of 360 T N F a MAb without coagulopathy at infusion, 107 [30.8%] of 347 placebo, p
'"1 I

60 Placebo

i

2ol

30 10

0'

I

0

7

I

I

14 21 Days after infusion Figure 2: Cumulative 28day survival estimates

I

28

were reported in 513 (54.1%) of 949 patients given T N F a MAb and 513 (55.2%) of 930 patients given placebo. Laboratory serum values before and after infusion were compared. There was no increase in the proportion of patients with abnormalities in renal (creatinine or blood urea nitrogen), hepatic (alanine aminotransferase, aspartate aminotransferase, . total bilirubin), pancreatic (lipase, amylase), or haematological (total white blood cell count, haemoglobin, prothrombin time, partial thromboplastin time, platelets) variables in, the two groups. The rate of bacterial superinfections or recovery from superinfections did not differ between groups. Serum sickness was reported in five (05%) T N F a MAb patients and one (0.1%) placebo patient. HAMA titres were positive in 59.7% of the patients given TNFa MAb. There was no apparent increase in adverse reactions among the seven patients with preformed HAMAs who received TNFa MAb.

We found no survival benefit among patients with septic shock treated with T N F a MAb and no evidence that TNFa MAb therapy shortened the length of the shock episode or hastened the resolution of sepsis-induced organ failure. Although there were significantly fewer episodes of subsequent coagulopathy among patients given TNFa MAb, no other organ or system failures seemed to be prevented. Even in the subgroup of patients with raised baseline plasma TNFa concentrations, TNFa MAb did not significantly increase survival at 28 days. Benefits for survival, rapidity of shock reversal, and development of subsequent organ system failure with the same monoclonal anti-TNF have been shown previously. The NORASEPT I study9 enrolled 478 prospectively identified patients with septic shock and found that the decrease in mortality associated with 7.5 mgkg TNFa MAb treatment compared with placebo was 49% 3 days after randomisation and 17% after 28 days. The INTERSEPT studyZoenrolled 420 patients with septic shock. That study investigated treatment with 15 mglkg and 3 mglkg TNFa MAb, which were associated with faster reversal of shock and development of organ or system failure in fewer patients at 28 days than placebo. In addition, the investigators found a trend towards decreased mortality at day 28 among patients treated with 3 mdkg T N F a MAb. We did not duplicate any of the findings of NORASEPT I or INTERSEPT. The discrepancies in results between NORASEPT I, INTERSEPT, and our trial do not seem to be due to differences in patient populations. In particular, day-28 mortality rates in the placebo groups were similar for patients with septic shock in all three studies (NORASEPT I 45.6%; INTERSEPT 42.9%; our study 42.8%). Similarly, in our trial and NORASEPT I, patients were well matched for mean APACHE I1 scores (28.5 vs 28.6), mean age (61.1 vs 59.1 years), proportion of men (58.2 vs 60.5%), mean shock duration (9.5 vs 8.3 h), and percentage of patients with one or more organ failures present at baseline (78.7 vs 89.1%). Nevertheless, survival patterns seem to differ substantially between these two studies, which may help to explain differences in the other results. More than 60% of the deaths in the placebo group of NORASEPT I occurred immediately after shock, within the first 3 days of study entry. In our study, the time to death in the placebo group was on average ~~~

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6.8 days. These differences in survival may reflect differences in study populations not apparent in analyses of baseline organ or system dysfunction and severity-ofillness scores. Improvements to the supportive care for septic shock made in the time between the two studies may have resulted in better survival from the initial hypotensive episode and associated immediate complications, a period in which proinflammatory cytokine release, including that for TNFa, may be greatest. If advances in management have permitted critically ill septic patients to survive longer in the initial state of accelerated cytokine expression, then the efficacy of therapies such as T N F a MAb in modulation of early proin~ammatoryresponse will be diminished. Clinical trials with other anti-TNFa agents, including F(ab')), fragments**and p55 TNF-receptor fusion protein constructs,'o suggest that populations more rigorously characterised than those in our study might benefit more from anti-TNFa therapy. For example, plasma interleukin-6 concentrations of more than 1000 pgi'mL have been proposedzs as predictors of response to antiTNFa treatment in sepsis. We found no such increase in efficacy among patients with concentrations of interleukin6 higher than this threshold at enrolment. A clinical trial investigating a p55 TNF-receptor IgG, fusion protein also found no correlation between concentrations of circulating interleukin-6 and treatment response.'O In the p55 TNFreceptor fusion protein study the greatest decrease in mortality was found among patients with septic shock of less than 6 h duration. In our study, 35.6% of patients in the TNFa MAb group and 34.9% in the placebo group had shock for 6 h or less at the time of infusion, but there was no significant relation between shock duration and response to T N F a MAb. Preclinical studieP'' that showed improved survival in animals with TNFa blockade generally gave anti-%Fa therapy before exposure to endotoxin or bacteria, or immediately after endotoxin or bacteria administration. Such early treatment is not possible in infected human beings, in whom clinical signs of a continuing infectious process are commonly present for hours to days before development of organ system dysfunction, including hypotension. We showed that TNFa blockade by monoclonal antibody therapy, even if provided within 12 h afier the development of hypotension and organ or system dysfunction, does not improve outcome in patients with septic shock. Although well-defined subgroups of patients with septic shock may respond to anti-TNF treatment, we identified no such subgroups. Rather, our results suggest that alternative therapeutic directions, not solely dependent on blockade of TNFa, may be required to improve survival of patients with septic shock. This study was supported by Bayer Corporation, Berkeley, California, USA

References 1 Wenzel RP.Anti-endotoxin monoclonal antibodies: a second look. NEnglJMed 1992; 326:1151-53. 2 Parrillo JE,Parker MM, Natanson C, et al. Septic shock in humans. Ann Intern Med 1990; 113: 227-42.

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3 Bone RC, Fisher CJ Jr, Clemmer TP, Sloman GJ, Metz CA,Balk RA. A controlled clinical trial of high-dose methylprednisolone in the treatment of severe sepsis and septic shock. N EnglJ Med 1987; 317: 653-58. 4 The HA-1A Sepsis Study Group. Treatment of gram negative bacteremia and septic shock with HA-IA human monoclonal antibody against endotoxin: a randomized, double-blind placebo-controlled mal. NEnglJMed 1991; 3 2 4 429-36. 5 Pamllo JE. M a n a g ~ e nof t septic shock: present and future. Ann Intern Med 1991; 115: 491-93. 6 Sands KE, Bates DW, Lanken PN, et 81. Epidemiology of sepsis syndrome in 8 academic medical centers. JAMA 1997; 2 7 8 234-40. 7 Rangel-Frausto MS, Pinet D, Costigan M, Hwang T, Davis CS, Wenzel RP.The natural history of the systemic inflammatory response syndrome (SIRS): a prospective study. J A M A 1995; 273: 117-23. 8 Bone RC, Fisher CJ Jr, Clemmer TP, et al. Sepsis syndrome: a valid clinical entity. Crir Care Med 1989; 17: 389-93. 9 Abraham E, Wunderink R, Silverman H, et al. Monoclonal antibody to human tumor necrosis factor alpha (TNFaMAb): efficacy and safety in patients with the sepsis syndrome. J A M 1995; 273: 93441. 10 Abraham E, Glauser MP, Butler T, et al. p55 tumor necrosis factor receptor fusion protein in the treatment of patients with severe sepsis and septic shock. J A M A 1997; 277: 1531-34. 11 Sherman ML, Spriggs DR, Arthur KA, et al. Recombinant human tumor necrosis factor administered as a five-day c o n ~ u infusion o ~ in cancer patients: phase I toxicity and effects on lipid metabolism. JClin Om01 1988; 6: 344-50. 12 Van der Poll T, Buller HR, Ten Cate HT. Activation of coagulation after administration of TNF to normal subjects. N Englr Med 1990; 322: 1622-27. 13 Michie HR,Manogue KR, Spriggs DR, et al. Detection of circulating tumor necrosis factor after endotoxin administration. N Engl J Med 1988; 318: 1481-86. 14 Cannon JG, Tompkins RG, Gelfand JA, et al. Circulating &I and T N F in septic shock and experimental endotoxin fever. J Infct Dis 1990; 161: 79-84. 15 Tracey KJ, Fong Y, Hesse DG, et al. Anti-cachectidllF monoclonal antibodies prevent septic shock during lethal bacteraemia. Nufure 1987; 3 3 0 662-64. 16 Fong Y, Tracey KJ, Moidawer LL,et al. Antibodies to cacheahTNF reduce interleukin-l and interleukin-6 appearance during lethal bacteremia. J Exp Med 1989; 1 7 0 1627-33. 17 Opal SM, Cross AS, Kelly NM, et al. Efficacy of a monoclonal antibody directed against T N F in protecting neutropenic rats from lethal infection with P. aeruginosa. J Infect Dis 199% 161: 1148-52. 18 Hinshaw LB,Tekamp-Olson P, Chang AC, et al. Survival of primates in LD,, septic shock following therapy with antibody to tumor necrosis factor (TNF). Circ Shock 1990; 3 0 279-92. 19 Hinshaw LB,Emerson TE Jr. Taylor FB Jr, et al. Lethal S. atrrars shock in primates: prevention of death with anti-TNF antibody. J Trauma 1992; 33: 568-73. 20 Cohen J, Carlet J. INTERSEPT: an international, multicenter, placebo-controlled trial of monoclonal antibody to human tumor necrosis factor a in patients with sepsis. Crit Cure Med 1996; 24: 143140. 21 Galloway CJ, Madanat MS, Mitra G. Monoclonal anti-tumor necrosis factor (TNF) antibodies protect mouse and human cells from TNF cytotoxicity. J I m ~ u M n ~ o d 1991; s 140: 3743. 22 Pauli U, Bertoni G, Duerr M, Peterhans E. A bioassay for the detection of NmOr necrosis factor from eight different species: evaluation of neutralization rates of a monoclonal antibody against human TNFa. J Immunol Methods 1994; 171: 263-65. 23 Knaus WA, Draper EA, Wagner DP, Zimmerman JE. APACHE 11: a severity of disease classification system. Crit Care Med 1985; 13: 818-28. 24 Tran DD, Groenveld ABJ, Meulen JVD,Nauta JJP, Suack van Schijndel RJM, Thijs LG. Age, chronic disease, sepsis, organ system failure and mortality in a medical intensive care unit. Cni Care 1990; 18: 474-79. 25 Reinhart K,Wiegand-Lohnert C, Grimmimger F, et al. Assessment of the safety and efficacy of the monoclonal anti-tumor necrosis factor antibody-fragment, MAK 195F, in patients with sepsis and septic shock a multicenter, randomized, placebo-controlled, dose-ranging study. Cnt Care Med 1996; 24: 733-42.

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