THE JOURNAL OF INFECTIOUS DISEASES. VOL. 140, xo. 1 • JULY 1979 © 1979 by The University of Chicago. 0022-1899/79/4001-0006$00.75
Simultaneous Administration of Live, Enteric-Coated Adenovirus Types 4,7, and 21 Vaccines: Safety and Immunogenicity From the Divisions of Preventive Medicine and of Communicable Disease and Immunology, The Walter Reed Army Institute of Research, Washington, D.C.
Ernest T. Takafuji,* Joel C. Gaydos, Richard G. Allen,'] and Franklin H. Top, Jr.
Adenoviruses have caused most of the febrile acute respiratory disease (ARD) found at military training centers [1-3]. Adenovirus type 4 (ADV-4) and type 7 (ADV-7) were the predominant serotypes causing ARD, and routine use of live, enteric-coated ADV-4 and ADV-7 vaccines resulted in significantly decreased rates of ARD [1, 4]. ARD due to adenovirus type 21 (ADV-2l)
was initially reported at traInIng camps in The Netherlands [5], and the first documented outbreak among U.S. soldiers occurred at Fort Dix, N.]., in 1967 [6]. Following this outbreak, ADV-21 was not again associated with outbreaks of ARD in the U.S. military forces until October 1975, when it was isolated from trainees at Fort Knox, Ky., and Fort Wood, :Mo. [7]. By the spring of 1976, ADV-2l had been isolated from trainees at all major U.S. Army basic-training centers and at a Navy training center, with hospitalization rates for ARD exceeding 2.0 per 100 trainees per week [7]. In 1971, a live, enteric-coated ADV-21 vaccine was evaluated for safety and immunogenicity in 45 volunteers [8, 9]. This vaccine was similar to the ADV-4 and ADV-7 vaccines in that it induced asymptomatic gastrointestinal infection and specific neutralizing (N) antibody. Because of the occurrence of disease due to ADV-21 in 1975 and 1976 in trainees immunized with ADV-4 and ADV-7 vaccines, the Surgeon General of the U.S. Army directed that the ADV-21 vaccine be tested further. This report presents data on the safety of and the immune response to ADV-4, ADV-7, and ADV-2 I vaccines given simultaneously to volunteers.
Received for publication May 15, 1978, and in revised form February 8, 1979. We thank the personnel of the U.S. Air Force Military Training Center and Wilford Hall Medical Center, Lackland Air Force Base, Texas, for their support and cooperation. Professional assistance was provided by Dr. Vicente Martinez, Lackland Air Force Base; Drs. George D. Lathrop and Louis Blouse, Jr., Brooks Air Force Base, Texas; and Drs. Richard A. Hodder, Douglas B. Tang, and Herbert E. Segal, The Walter Reed Army Institute of Research, Washington, D.C. We thank M. C. Callahan, L. C. Evans, D. A. Leach, H. G. Cannon, B. H. Robinson, J. R. Putnak, K. V. Belleville, and V. Kelley for technical assistance. Please address requests for reprints to Dr. Joel C. Gaydos, Division of Preventive Medicine, The Walter Reed Army Institute of Research, Washington, D.C. 20012. ,.. Present address: U.S. Army Medical Department Activity, Fort Bragg, North Carolina. t Present address: U.S. Army Medical Research Institute of Infectious Diseases, Fort Detrick, Maryland.
48
Downloaded from http://jid.oxfordjournals.org/ at University of Birmingham on June 4, 2015
The safety of and the immune response to simultaneous administration of live, enteric-coated adenovirus type 4 (ADV-4), type 7 (ADV-7), and type 21 (ADV-21) vaccines were studied. Volunteers (476 men), randomly assigned to four study groups, received three vaccines (ADV-4, ADV-7, and ADV-21), two vaccines (ADV4 and ADV-7), one vaccine (ADV-21), or no vaccine (placebo). Subjects were observed for three weeks, and no side effects due to vaccination occurred. The percentages of susceptible subjects (those entering the study with a neutralizing antibody titer of 0.1).
ADV-21 Vaccine: Safety and Immune Response
Materials and Methods
tv
impractical, but an attempt was made to obtain comparable numbers of susceptibles in each vaccine group. The expected percentages of susceptibles in each group were obtained from the study of a simple random sample of unimmunized recruits in basic training (288 men) at Fort Jackson, S.C., and Fort Knox, Ky., in Marc? 1976. 1 Among these trainees, 40% lacked N antibody to ADV-4, ADV-7, and ADV-21; 89~o lacke? N antibody to ADV-21; and 42~o lacked N antibody to ADV-4 or ADV-7. On the basis of these data, 157 volunteers were assigned to group 4/7/21, 68 to group p/p/21, and 149 to group 4/7/p. The 102 volunteers assigned to the pi pip group were expected to include 78 individuals initially lacking antibody to ADV-4, 55 lacking antibody to ADV-7, and 91 lacking antibody to ADV-21. Combinations of vaccine and placebo tablets for the study groups were prepackaged in sequentially numbered envelopes; study groups were assigned envelopes with use of a table of random numbers. Neither the volunteers nor the field investigators knew the contents of specific envelopes. Volunteers received study number~ in s~ quential order and, in the presence of an mvestigator, swallowed the tablets from the envelope that had their study number. Blood specimens for antibody testing were obtained before vaccination and 21-25 days after vaccination. Disease surveillance of participants was conducted for 21 days. Disease surveillance. The safety of the various vaccine regimens was determined by observation of participants to detect any illnesses. Outpatient and hospital logs were checked daily, and the medical records of the trainees were examined in the middle and at the end of the study period. At the conclusion of the study, qu~stio~ naires were administered to volunteers to Identify any additional illnesses that might have occurred during the study. Hospitalizations included all admissions to the base hospital or to an intermediate-care facility. Decisions to hospitalize study participants were 1 J. C. Gaydos, R. A. Hodder, R. G. Allen, H. E.. Seg~l, V. J. Soden, and F. H. Top, Jr., "Prevalence of Antibodies to Adenovirus Serotypes in Unimmunized U.S. Army Recruits," manuscript in preparation.
Downloaded from http://jid.oxfordjournals.org/ at University of Birmingham on June 4, 2015
Volunteer population. Lackland Air Force Base, Tex., was selected as the study site because ongoing surveillance had revealed a low inc~ dence of ARD due to adenovirus and no eVIdence of infection with ADV-21 prior to the study. In August 1976, 476 males who were 17 years of age or older and in their first or second day of basic training volunteered for the stu~~. The study was explained thoroughly to partICIpants, and all of the volunteers gave written consent. Vaccines. Enteric-coated tablets containing the live vaccine viruses were obtained from Wyeth Laboratories, Philadelphia, Pa. (ADV-4, lot no. 98A2621; ADV-7, lot no. 98A2622; and ADV21, lot no. 98A2875). Prior to administration, the titers of the vaccine were 5.4, 7.2, and 5.9 10g10 TCID 50 in primary human embryonic kidney (HEK) cell cultures for ADV-4, ADV-7, and ADV-21, respectively. Vaccine tablets were refrigerated until administration to the volunteers. Study design. Recruits in basic training ro~ tinely received ADV-4 and ADV-7 vaccines SImultaneously soon after their arrival at training centers. To compare the existing program with one in which ADV-4, ADV-7, and ADV-21 vaccines were administered together and to evaluate the ADV-21 vaccine when given alone, we studied four groups of volunteers. Group 4/7/21 received ADV-4, ADV-7, and ADV-21 vaccines; group p/p/21, two placebo tablets and ADV21 vaccine; group 4/7/p, ADV-4 and ADV-7 vaccines and one placebo tablet; and group plplp, three placebo tablets. Consistent with the policy of The Walter Reed Army Institute of Research, Washington, D.C., the number of volunteers who received the ADV-21 vaccine in this study was limited to 225, five times the number of people who had been immunized previously with ADV-21 vaccine. For this reason, other vaccine groups (e.g., 4/21 and 7/21 Ip) were not included. N antibody responses of susceptibles, subjects lacking preexisting antibody (titer, < 1:2) to the vaccine virus or to all of the vaccine viruses received, were used as the measure of vaccine immunogenicity in this study. Determination of the antibody status of volunteers before the study was
49
Takafuji et al,
50
dilution of 1:2 for N antibodies to strains of vaccine virus. Sera obtained before and after vaccination from volunteers in group 4/7/21 who lacked preexisting N antibody (titer, < I :2) to all three vaccine viruses, from volunteers in group p/p/21 who lacked preexisting N antibody to ADV-21, and from volunteers in group 4/7/p who lacked preexisting N antibody to ADV-4 and ADV-7 were tested for N antibody to the vaccine virus or viruses received. Initial and three-week sera from volunteers in group p/p/p were tested for N antibody to the adenovirus or adenoviruses to which no detectable antibody had been found at the beginning of the study. Titers of > 1:32 were not determined because of a lack of HEK cell cultures. The immune response of volunteers with preexisting N antibody to any vaccine virus received was not studied for the same reason.
Results
Volunteer population. Fifteen of the 476 volunteers did not complete the study; all 15 terminated basic training prematurely because of preexisting medical conditions or for other reasons unrelated to this study. The percentages of volunteers terminating basic training during the study period were not appreciably different from those observed in other trainee populations at Lackland Air Force Base and were similar for the four study groups (1.3% for group 4/7/21,
Table 1. Hospitalizations and outpatient episodes among volunteers by type of illness during the three-week trial of adenovirus (ADV) type 4, type 7, and type 21 vaccines (Lackland Air Force Base, Tex., 1976). Hospitalizations Study group (no.}" 4/7/21 (156) p/p/21 (65) 4/7/p (146) (101)
vtvt»
Total (468)
Acute respiratory disease
Gastrointestinal disease
(3.2) (1.5) (1.4) (3.0)
0(0) 0(0) 2 (1.4) 2 (2.0)
11 (2.4)
4 (0.8)
5 1 2 3
Outpatient episodes Other illness 6 1 3 1
(3.8) (1.5) (2.0) (1.0)
11 (2.4)
Acute respiratory illness 26 5 21 20
(16.7) (7.7) (14.4) (19.8)
72 (15.4)
Gastrointestinal disease 5 3 8 4
(3.2) (4.6) (5.5) (4.0)
20 (4.3)
Other illness 45 17 35 32
(28.8) (26.2) (24.0, (31. 7)
129 (27.6)
NOTE. Group 4/7/21 received ADV-4. ADV-7. and ADV-21 vaccines; group p/p/21, two placebo tablets and ADV·21 vaccine; group 417/p, ADV·4 and ADV-7 vaccines and one placebo tablet; and group p/p/p, three placebo tablets. Data are given as number of volunteers (percentage). *Number in study group halfway through the study period.
Downloaded from http://jid.oxfordjournals.org/ at University of Birmingham on June 4, 2015
made by physicians not involved in the investigation. Outpatient visits were tabulated as "outpatient episodes." An outpatient episode was one or more outpatient visits by the same volunteer for the same medical problem during a one-week period. Outpatient visits for acute respiratory illness included visits for conditions characterized by rhinitis, sore throat, or cough. ARD included any of the above respiratory symptoms in addition to an oral temperature of ~100 F (the policy of Lackland Air Force Base required hospitalization of any trainee with a temperature of ~100 F). Specimens for isolation of adenoviruses were obtained only from hospitalized volunteers. Pharyngeal swabs were collected from volunteers with ARD; throat and rectal swabs were obtained from volunteers with symptoms of gastrointestinal disease. Viral specimens were maintained at ambient temperature (about 24 C) in Leibovitz's charcoal transport media [3] prior to inoculation in HEK cells. Cultures were observed every other day and were maintained for 21 days. Acute- and two-week convalescent-phase sera for testing for N antibodies toadenoviruses were obtained only from volunteers hospitalized for ARD or for gastrointestinal disease. Antibody response. All tests for N antibody to adenoviruses were done in HEK cells by methods described in earlier studies [8, 9], and the cultures were read when the test dose of virus was between 10 and 100 TCID50. Sera initially obtained from all volunteers were screened at a
ADV·21 Vaccine: Safety and Immune Response
51
Table 2. Titers of neutralizing antibody to adenovirus (ADV) antigens after vaccination with live, enteric vaccine in volunteers who had an initial titer of
Simultaneous Administration of Live, Enteric-Coated Adenovirus Types 4,7, and 21 Vaccines: Safety and Immunogenicity From the Divisions of Preventive Medicine and of Communicable Disease and Immunology, The Walter Reed Army Institute of Research, Washington, D.C.
Ernest T. Takafuji,* Joel C. Gaydos, Richard G. Allen,'] and Franklin H. Top, Jr.
Adenoviruses have caused most of the febrile acute respiratory disease (ARD) found at military training centers [1-3]. Adenovirus type 4 (ADV-4) and type 7 (ADV-7) were the predominant serotypes causing ARD, and routine use of live, enteric-coated ADV-4 and ADV-7 vaccines resulted in significantly decreased rates of ARD [1, 4]. ARD due to adenovirus type 21 (ADV-2l)
was initially reported at traInIng camps in The Netherlands [5], and the first documented outbreak among U.S. soldiers occurred at Fort Dix, N.]., in 1967 [6]. Following this outbreak, ADV-21 was not again associated with outbreaks of ARD in the U.S. military forces until October 1975, when it was isolated from trainees at Fort Knox, Ky., and Fort Wood, :Mo. [7]. By the spring of 1976, ADV-2l had been isolated from trainees at all major U.S. Army basic-training centers and at a Navy training center, with hospitalization rates for ARD exceeding 2.0 per 100 trainees per week [7]. In 1971, a live, enteric-coated ADV-21 vaccine was evaluated for safety and immunogenicity in 45 volunteers [8, 9]. This vaccine was similar to the ADV-4 and ADV-7 vaccines in that it induced asymptomatic gastrointestinal infection and specific neutralizing (N) antibody. Because of the occurrence of disease due to ADV-21 in 1975 and 1976 in trainees immunized with ADV-4 and ADV-7 vaccines, the Surgeon General of the U.S. Army directed that the ADV-21 vaccine be tested further. This report presents data on the safety of and the immune response to ADV-4, ADV-7, and ADV-2 I vaccines given simultaneously to volunteers.
Received for publication May 15, 1978, and in revised form February 8, 1979. We thank the personnel of the U.S. Air Force Military Training Center and Wilford Hall Medical Center, Lackland Air Force Base, Texas, for their support and cooperation. Professional assistance was provided by Dr. Vicente Martinez, Lackland Air Force Base; Drs. George D. Lathrop and Louis Blouse, Jr., Brooks Air Force Base, Texas; and Drs. Richard A. Hodder, Douglas B. Tang, and Herbert E. Segal, The Walter Reed Army Institute of Research, Washington, D.C. We thank M. C. Callahan, L. C. Evans, D. A. Leach, H. G. Cannon, B. H. Robinson, J. R. Putnak, K. V. Belleville, and V. Kelley for technical assistance. Please address requests for reprints to Dr. Joel C. Gaydos, Division of Preventive Medicine, The Walter Reed Army Institute of Research, Washington, D.C. 20012. ,.. Present address: U.S. Army Medical Department Activity, Fort Bragg, North Carolina. t Present address: U.S. Army Medical Research Institute of Infectious Diseases, Fort Detrick, Maryland.
48
Downloaded from http://jid.oxfordjournals.org/ at University of Birmingham on June 4, 2015
The safety of and the immune response to simultaneous administration of live, enteric-coated adenovirus type 4 (ADV-4), type 7 (ADV-7), and type 21 (ADV-21) vaccines were studied. Volunteers (476 men), randomly assigned to four study groups, received three vaccines (ADV-4, ADV-7, and ADV-21), two vaccines (ADV4 and ADV-7), one vaccine (ADV-21), or no vaccine (placebo). Subjects were observed for three weeks, and no side effects due to vaccination occurred. The percentages of susceptible subjects (those entering the study with a neutralizing antibody titer of 0.1).
ADV-21 Vaccine: Safety and Immune Response
Materials and Methods
tv
impractical, but an attempt was made to obtain comparable numbers of susceptibles in each vaccine group. The expected percentages of susceptibles in each group were obtained from the study of a simple random sample of unimmunized recruits in basic training (288 men) at Fort Jackson, S.C., and Fort Knox, Ky., in Marc? 1976. 1 Among these trainees, 40% lacked N antibody to ADV-4, ADV-7, and ADV-21; 89~o lacke? N antibody to ADV-21; and 42~o lacked N antibody to ADV-4 or ADV-7. On the basis of these data, 157 volunteers were assigned to group 4/7/21, 68 to group p/p/21, and 149 to group 4/7/p. The 102 volunteers assigned to the pi pip group were expected to include 78 individuals initially lacking antibody to ADV-4, 55 lacking antibody to ADV-7, and 91 lacking antibody to ADV-21. Combinations of vaccine and placebo tablets for the study groups were prepackaged in sequentially numbered envelopes; study groups were assigned envelopes with use of a table of random numbers. Neither the volunteers nor the field investigators knew the contents of specific envelopes. Volunteers received study number~ in s~ quential order and, in the presence of an mvestigator, swallowed the tablets from the envelope that had their study number. Blood specimens for antibody testing were obtained before vaccination and 21-25 days after vaccination. Disease surveillance of participants was conducted for 21 days. Disease surveillance. The safety of the various vaccine regimens was determined by observation of participants to detect any illnesses. Outpatient and hospital logs were checked daily, and the medical records of the trainees were examined in the middle and at the end of the study period. At the conclusion of the study, qu~stio~ naires were administered to volunteers to Identify any additional illnesses that might have occurred during the study. Hospitalizations included all admissions to the base hospital or to an intermediate-care facility. Decisions to hospitalize study participants were 1 J. C. Gaydos, R. A. Hodder, R. G. Allen, H. E.. Seg~l, V. J. Soden, and F. H. Top, Jr., "Prevalence of Antibodies to Adenovirus Serotypes in Unimmunized U.S. Army Recruits," manuscript in preparation.
Downloaded from http://jid.oxfordjournals.org/ at University of Birmingham on June 4, 2015
Volunteer population. Lackland Air Force Base, Tex., was selected as the study site because ongoing surveillance had revealed a low inc~ dence of ARD due to adenovirus and no eVIdence of infection with ADV-21 prior to the study. In August 1976, 476 males who were 17 years of age or older and in their first or second day of basic training volunteered for the stu~~. The study was explained thoroughly to partICIpants, and all of the volunteers gave written consent. Vaccines. Enteric-coated tablets containing the live vaccine viruses were obtained from Wyeth Laboratories, Philadelphia, Pa. (ADV-4, lot no. 98A2621; ADV-7, lot no. 98A2622; and ADV21, lot no. 98A2875). Prior to administration, the titers of the vaccine were 5.4, 7.2, and 5.9 10g10 TCID 50 in primary human embryonic kidney (HEK) cell cultures for ADV-4, ADV-7, and ADV-21, respectively. Vaccine tablets were refrigerated until administration to the volunteers. Study design. Recruits in basic training ro~ tinely received ADV-4 and ADV-7 vaccines SImultaneously soon after their arrival at training centers. To compare the existing program with one in which ADV-4, ADV-7, and ADV-21 vaccines were administered together and to evaluate the ADV-21 vaccine when given alone, we studied four groups of volunteers. Group 4/7/21 received ADV-4, ADV-7, and ADV-21 vaccines; group p/p/21, two placebo tablets and ADV21 vaccine; group 4/7/p, ADV-4 and ADV-7 vaccines and one placebo tablet; and group plplp, three placebo tablets. Consistent with the policy of The Walter Reed Army Institute of Research, Washington, D.C., the number of volunteers who received the ADV-21 vaccine in this study was limited to 225, five times the number of people who had been immunized previously with ADV-21 vaccine. For this reason, other vaccine groups (e.g., 4/21 and 7/21 Ip) were not included. N antibody responses of susceptibles, subjects lacking preexisting antibody (titer, < 1:2) to the vaccine virus or to all of the vaccine viruses received, were used as the measure of vaccine immunogenicity in this study. Determination of the antibody status of volunteers before the study was
49
Takafuji et al,
50
dilution of 1:2 for N antibodies to strains of vaccine virus. Sera obtained before and after vaccination from volunteers in group 4/7/21 who lacked preexisting N antibody (titer, < I :2) to all three vaccine viruses, from volunteers in group p/p/21 who lacked preexisting N antibody to ADV-21, and from volunteers in group 4/7/p who lacked preexisting N antibody to ADV-4 and ADV-7 were tested for N antibody to the vaccine virus or viruses received. Initial and three-week sera from volunteers in group p/p/p were tested for N antibody to the adenovirus or adenoviruses to which no detectable antibody had been found at the beginning of the study. Titers of > 1:32 were not determined because of a lack of HEK cell cultures. The immune response of volunteers with preexisting N antibody to any vaccine virus received was not studied for the same reason.
Results
Volunteer population. Fifteen of the 476 volunteers did not complete the study; all 15 terminated basic training prematurely because of preexisting medical conditions or for other reasons unrelated to this study. The percentages of volunteers terminating basic training during the study period were not appreciably different from those observed in other trainee populations at Lackland Air Force Base and were similar for the four study groups (1.3% for group 4/7/21,
Table 1. Hospitalizations and outpatient episodes among volunteers by type of illness during the three-week trial of adenovirus (ADV) type 4, type 7, and type 21 vaccines (Lackland Air Force Base, Tex., 1976). Hospitalizations Study group (no.}" 4/7/21 (156) p/p/21 (65) 4/7/p (146) (101)
vtvt»
Total (468)
Acute respiratory disease
Gastrointestinal disease
(3.2) (1.5) (1.4) (3.0)
0(0) 0(0) 2 (1.4) 2 (2.0)
11 (2.4)
4 (0.8)
5 1 2 3
Outpatient episodes Other illness 6 1 3 1
(3.8) (1.5) (2.0) (1.0)
11 (2.4)
Acute respiratory illness 26 5 21 20
(16.7) (7.7) (14.4) (19.8)
72 (15.4)
Gastrointestinal disease 5 3 8 4
(3.2) (4.6) (5.5) (4.0)
20 (4.3)
Other illness 45 17 35 32
(28.8) (26.2) (24.0, (31. 7)
129 (27.6)
NOTE. Group 4/7/21 received ADV-4. ADV-7. and ADV-21 vaccines; group p/p/21, two placebo tablets and ADV·21 vaccine; group 417/p, ADV·4 and ADV-7 vaccines and one placebo tablet; and group p/p/p, three placebo tablets. Data are given as number of volunteers (percentage). *Number in study group halfway through the study period.
Downloaded from http://jid.oxfordjournals.org/ at University of Birmingham on June 4, 2015
made by physicians not involved in the investigation. Outpatient visits were tabulated as "outpatient episodes." An outpatient episode was one or more outpatient visits by the same volunteer for the same medical problem during a one-week period. Outpatient visits for acute respiratory illness included visits for conditions characterized by rhinitis, sore throat, or cough. ARD included any of the above respiratory symptoms in addition to an oral temperature of ~100 F (the policy of Lackland Air Force Base required hospitalization of any trainee with a temperature of ~100 F). Specimens for isolation of adenoviruses were obtained only from hospitalized volunteers. Pharyngeal swabs were collected from volunteers with ARD; throat and rectal swabs were obtained from volunteers with symptoms of gastrointestinal disease. Viral specimens were maintained at ambient temperature (about 24 C) in Leibovitz's charcoal transport media [3] prior to inoculation in HEK cells. Cultures were observed every other day and were maintained for 21 days. Acute- and two-week convalescent-phase sera for testing for N antibodies toadenoviruses were obtained only from volunteers hospitalized for ARD or for gastrointestinal disease. Antibody response. All tests for N antibody to adenoviruses were done in HEK cells by methods described in earlier studies [8, 9], and the cultures were read when the test dose of virus was between 10 and 100 TCID50. Sera initially obtained from all volunteers were screened at a
ADV·21 Vaccine: Safety and Immune Response
51
Table 2. Titers of neutralizing antibody to adenovirus (ADV) antigens after vaccination with live, enteric vaccine in volunteers who had an initial titer of
