Patients enrolled in clinical trial
Out of 162 HIV + MSM patients undergoing screening from May 15 2012 through May 15 2014, 30 (18.5%) did not meet inclusion criteria and 3 (1.85%) withdrew their consent. The 129 patients in the final study sample were randomly assigned to the vaccine arm (n = 66, 51.2%) or placebo arm (n = 63, 48.4%). Among the 66 participants in the vaccine arm, 64 (96.9%) received all three doses of the vaccine and the remaining 2 participants only two doses, due to death from liver cirrhosis at 6 months post-enrolment and relocation to another city, respectively. Follow-up was completed by 110 (85.3%) participants, with a median of 48 months (P25: 36-P75 48), but not by 19 (14.7%), due to non-AIDS-defining disease in two cases (10.5%; lung cancer in 1 and decompensated liver cirrhosis in 1), with the remaining 17 (89.4%) being lost to the follow up (Fig. 1).
The mean age of the participants was 38.8 years, 69 (53.5%) had completed university studies, their sexual life had started a median of 19 years earlier, 40 (31%) had a history of AIDS, 119 (92.2%) were receiving antiretroviral treatment, and only 4 (3.3%) had virological failure. Table 1 lists the results for remaining variables, showing that patients in each arm were similar in age, social strata, educational level, sexual habits, consumption of toxic substances, other infections, and HIV-related data (virological and immunological status).
Table 1
Baseline demographics of HIV-positive MSM enrolled in the clinical trial
| Total Cohort of HIV-MSM (n = 129) | HIV-MSM Vaccine (n = 66) | HIV-MSM Placebo (n = 63) | P* |
Age, years; mean (± SD) | 38.8((± 10.4) | 37.3 (± 10.6) | 40.5 (± 10.02) | 0.082 |
Spanish nationality, n (%) University education, n (%) | 123(95.3) 69 (53.5) | 63 (95.5) 34 (51.5) | 60 (95.2) 35 (55.5) | 0.2 0.56 |
Partners in previous 12 months; median (IQR) Life-time partners; n, median (IQR) Years of sexual activity; median (IQR) | 1 (1-3.75) 72.5(20.5–300) 19 (10–27) | 1 (1–3) 50 (20–300) 17 (9–24) | 1 (1–5) 100 (45–350) 21 (13–27) | 0.8 0.041* 0.025* |
Condom use, n (%) | 100 (77.5) | 53 (80.3) | 47 (74.6) | 0.4 |
Perianal/genital condylomas at screening, n (%) | 40 (31) | 20 (30.3) | 20 (31.7) | 0.86 |
History of condylomas, n (%) | 34 (26.4) | 19 (28.8) | 15 (23.8) | 0.52 |
Duration of HIV; mean months (IQR) | 67.5(31-123.5) | 58 (26–120) | 77 (37–138) | 0.2 |
History of AIDS; n (%) | 40 (31) | 19 (28.8) | 21 (33.3) | 0.58 |
CD4 mean nadir; cells/µL (± SD) | 335,12 (± 210.9) | 336(± 227.3) | 334.2(± 193.7) | 0.96 |
CD4 mean; cells/µL (± SD) | 721.9 (± 258.8) | 733(± 252.7) | 710.4 (± 266.6) | 0.62 |
CD8 mean; cells/µL (± SD) | 996.2 (± 422.04) | 999.9(± 463.6) | 992.2(± 374.9) | 0.98 |
VL of HIV log10; copies/mL (± SD) VL < 50 copies/mL, n (%) | 3.72 (± 4.84) 106(82.2) | 3.76 (± 4.5) 53 (80.3) | 3.67 (± 4.46) 53 (84.1) | 0.8 0.57 |
Virological failure, n (%) ART, n(%) | 4 (3.3) 119 (92.2) | 1 (1.5) 60 (90.9) | 3 (4.8) 59 (93.7) | 0.29 0.745 |
Median duration of ART; months (IQR) Number of lines of ART, median (IQR) | 45 (17-101.25) 1 (1–2) | 42 (17–86) 1 (1–2) | 43 (17–129) 1 (1–2) | 0.42 0.56 |
Syphilis treated, n (%) Other STD, n (%) | 28 (21.7) 23 (17.8) | 16 (24.2) 11 (16.6) | 12(19.1) 12 (19.1) | 0.47 0.72 |
Latent tuberculosis treated, n (%) | 15(11.6) | 5 (7.6) | 10(15.9) | 0.14 |
HCV, n (%) | 4 (3.1) | 2 (3) | 2 (3.2) | 1 |
HBV, n (%) Smoking, packs/year, median (IQR) Ex-smoking, n(%) Ex-IVDA, n (%) Alcohol (standard units of alcohol; SUA) | 2 (1.6) 1.9 (0-12.5) 23 (17.8) 1 (0.8) 0.16(0–1) | 2 (3) 0.2 (0–1) 10 (15) 1 (1.5) 0 (0–1) | 0 (0) 6,5 (0–18) 13 (20.6) 0 (0) 0.4 (0-1.4) | 0.49 0.008* 0.42 0.42 0.15 |
P*: p-value; p < 0.05 |
ART: antiretroviral therapy. VL: viral load; Ex-IDVA: ex-injection drug venous addiction. |
* FDR correction for multiple comparisons showed that difference was not statistically significant. |
With respect to anal infection by HPV genotype, 90 (73.8%) patients were infected with high-risk genotypes, 73 (59.8%) with low-risk genotypes, and 59 (48.4%) with both types of virus; 30 (24.6%) were infected with genotype 16, 19 (15.6%) with genotype 6, 15 (12.6%) with genotype 11, and 9 (7.4%) with genotype 18. Cytology results were normal in 53 (41.1%) patients and revealed LSIL in 60 (46.5%), HSIL in 5 (3.9%), and ASC-US in 11 (8.5%). Anal biopsy evidenced LSIL/AIN1 in 62 patients (48.1%) and was normal in 67 (51.9%). There was no between-group difference in genotype infection or in cytology or histological results (Table 2).
Table 2
Baseline HPV PCR, cytology, and HRA* results in the study population
Variable | Total cohort of HIV-MSM (n = 122) | HIV-MSM Vaccine (n = 65) | HIV-MSM Placebo (n = 57) | P* |
PCR of HPV, n (%) LR-HPV | 73 (59.8) | 39 (60) | 34 (59.6) | 0.97 |
HR-HPV | 90 (73.8) | 46 (70.8) | 44 (77.2) | 0.42 |
LR and HR HPV, n (%) | 59 (48.4) | 28 (43.1) | 31 (54.4) | 0.21 |
Number of HR-HPVs (IQR) | 1 (0–3) | 1 (0–2) | 2 (0–3) | 0.22 |
Number of LR-HPVs (IQR) | 1 (0–2) | 1 (0–2) | 1 (0–2) | 0.94 |
Genotypes, n (%) | | | | |
HPV6 | 19 (15.6) | 11 (16.9) | 8 (14) | 0.66 |
HPV11 | 15 (12.6) | 8 (12.3) | 7 (12.3) | 0.99 |
HPV16 HPV16 species | 30 (24.6) 46 (37.8) | 15 (23.1) 22 (33.3) | 15 (26.3) 24 (38.1) | 0.68 0.49 |
HPV18 HPV18 species | 9 (7.4) 40 (32.8) | 4 (6.2) 18 (27.3) | 5 (8.8) 22 (34.9) | 0.58 0.35 |
Cytology, n (%) Normal LSIL HSIL ASCUS | 53 (41.1) 60 (46.5) 5 (3.9) 11 (8.5) | 26 (39.4) 34 (51.5) 1 (1.5) 5 (7.6) | 27 (42.9) 26 (41.3) 4 (6.3) 6 (9.5) | 0.69 0.24 0.21 0.69 |
HRA, n (%) Normal LSIL(AIN1) | 67 (51.9) 62 (48.1) | 33 (50) 33 (50) | 29 (46) 34 (54) | 0.65 0.65 |
HRA*: high resolution anoscopy. |
P**: p-value; p < 0.05 |
In relation to the prevalence of HSILs and ASCC during the follow-up of the global cohort, it was 10.5% (13/124) and 0.8% (1/124), respectively, at 12 months, in 0.95% (1/105) and 0% at 24 months, in 1.02% (1/98) and 0% at 36 months, and in 1.075% (1/93) and 0%, respectively, at 48 months. The difference in ≥ HSIL prevalence between 12 months (11.3% [14 /124]) and 48 months. 1.07% [1/93] was statistically significant (p < 0.0001). There was also a decrease in the incidence of HSILs and ASCC, which was 104.8 × 1000 p-year and 806.45 × 100.000 p-year, respectively, at 12 months of follow-up, 62.8 × 1000 p-year and 448.4 × 100.000 p-year at 24 months, 48.54 × 1000 p-year and 323.64 × 100.000 p-year at 36 months; and 41.03 × 1000 p-year and 256.4 × 100.000 p-year at 48 months. The difference in the incidence of ≥ HSIL between 12 months and 48 months was also statistically significant (p < 0.0001). The only case of invasive perianal cancer was diagnosed in a patient who had been vaccinated 6 months earlier; it debuted with a hardened perianal lesion and a metastatic cervical lymph node in which high-risk genotype 33 was detected. Despite receiving chemotherapy and radiotherapy, he died at 12 months.
Efficacy of qHPV vaccine
The ≥ HSIL rate did not significantly differ between vaccinated and placebo groups during the 48-month follow-up (9 [14.1%] vs. 8 [13.1%], respectively, p = 0.87), finding no difference at 12 months (7/63 [11.1%] vs. placebo 7/61 [11.5%], respectively; p = 1); 24 months (0% vs. 2% [1/50], p = 0.472); 36 months (1.9% [1/53] vs. 0%, p = 1), or 48 months (2% [1/50] vs. 0%, p = 1).
During the 48-month follow-up, vaccine and placebo arms did not differ in the prevention of EAGLs/condylomas (9 [14.3%] vs. 8 [13.6%], respectively, p = 0.98), which were detected in 6.3% (4/63) of the vaccine group vs. 5.2% (3/58) of the placebo group at 12 months (p = 1), in 9.4% (5/53) vs. 5.9% (3/51), respectively, at 24 months (p = 0.72); in 8% (4/50) vs. 4.4% (2/45) at 36 months (p = 0.68); and in 6.4% (3/47) vs. 2.6% (1/38) at 48 months (p = 0.63). However, a significant decrease (p < 0.0001) was observed in the whole cohort between the prevalence of these lesions at study enrolment (31%, 40/129) and at the end of the follow-up (4.3%, 4/93)
No significant between-arm difference was found in the acquisition of the qHPV genotypes at 12 months with the exception of VPH-6, which was observed in 4 (7.5%) of the vaccine group vs. 11 (23.4%) of the placebo group (p = 0.047), detecting VPH 11 in 4 (7.7%) vs. 3 (6.3%), respectively (p = 1), VPH-16 in 12 (25.5%) vs. 10 (24.4%) (p = 1), and VPH-18 in 9 (15.8%) vs. 6 (11.8%) (p = 0.546); at 24 months, detecting VPH-6 in 4 (8.3%) vs. 2 (5.3%), respectively (p = 0.69), VPH-11 in 6 (13%) vs. 1 (2.3%) (p = 0.112), VPH-16 in 3 (9.4%) vs. 4 (11.1%) (p = 1), and VPH-18 in 3 (6.1%) vs. 1 (2.25) (p = 0.618); at 36 months, detecting VPH-6 in 1 (2.7%) vs. 3 (8.8%) (p = 0.34), VPH-11 in 2 (5.1%) vs. 0 (p = 0.49), VPH-16 in 4 (11.8%) vs. 1 (3.3%) (p = 0.36), and VPH-18 in 2 (4.7%) vs. 0 (p = 0.49); or at 48 months, detecting VPH-6 in 3 (9.1%) vs. 1 (3.7%) (p = 0.62), VPH-11 in 0 vs. 0; VPH-16 in 2 (6.7%) vs. 1 (3.8%) (p = 1), and VPH-18 in 2 (6.3%) vs. 0 (p = 0.493).
Immunogenicity of qHPV vaccine
Antibodies against qHPV vaccine genotypes were detected in 76.9% (50/65) of the vaccine group vs. 30.2% (19/63) of the placebo group at 7 months (p < 0.0001), in 68.1% (32/47) vs. 26.5% (13/50) at 12 months (p < 0.0001), in 75% (36/48) vs. 32.5% (13/40) at 24 months (p = 0.0001); in 90% (45/50) vs. 24.4% (10/41) at 36 months (p < 0.0001); and in 87.2% (41/47) vs. 30% (12/40) at 48 months (p < 0.0001). The antibodies remained stable throughout the follow up.
Factors related to ≥ HSIL onset
The sole factor significantly associated with the risk of anal ≥ HSIL onset during the two-year follow-up was the receipt of the last dose of the vaccine less than 6 months earlier in comparison to those vaccinated for a longer period (82.4% vs. 17.6% (OR 0.869 [95% CI, 0.825–0.917]). Results for the remaining study variables are exhibited in Table 3.
Table 3
Bivariate and multivariate analyses of factors associated with ≥ HSILs
Factors | HIV-MSM with ≥ HSIL (n = 17) | HIV-MSM without ≥ HSIL (n = 107) | P* | RR; (95% CI) |
q-HPV Vaccine, n(%) | 9 (52.9) | 55 (50.9) | 0.877 | |
Ab q-HPV Vaccine, n(%) 7 months 12 months 24 months 36 months 48 months Titers Ab 7 m, median (IQR) Titers Ab 12 m, median (IQR) | 9 (52.9) 8 (53.3) 2 (100) 1 (50) 0 2.21 (1.78–4.39) 3.48 (2.26–3.65) | 58 (54.2) 37 (45.1) 47 (54.7) 54 (60.7) 53 (61.6) 3.46 (1.7–5.1) 2.39 (0-4.53) | 0.92 0.56 0.2 1 0.391 0.41 0.65 | |
Interval between first dose and HSIL onset, IQR | 12 (12–12) | 48 (48–48) | 0.0001 | 0.869 (0.825–0.917) |
Age; mean years (± SD) | 39 (10.98) | 38.54 (10.28) | 0.620 | |
Median HR- HPV, (IQR) Median LR-HPV, (IQR) | 1 (0–4) 1 (0–2) | 1 (0–3) 1 (0–2) | 0.454 0.625 | |
University education, n (%) Retired, n(%) | 8 (47.1) 2 (11.8) | 59 (54.6) 11 (10.2) | 0.626 0.69 | |
Partners in previous 12 months; median (IQR) Life-time partners; median (IQR) Time since start of sexual activity (years); median (IQR) | 1 (0.5–2.5) 100 (15–325) 21 (11–28)18.5 | 1 (1–4) 70 (22.75–300) 18.5(10–27) | 0.394 0.988 0.552 | |
Condom use, n (%) % condom use; median (IQR) | 13 (76.5) 99 (5-100) | 84 (77.8) 100 (52.5–100) | 1 0.289 | |
Perianal/genital condyloma, n (%) | 7 (41.2) | 32 (29.6) | 0.4 | |
History of condyloma, n (%) | 2 (11.8) | 31 (28.7) | 0.235 | |
Smoking, n(%) Smoking, packs/year; median (IQR) Ex-smoker, n (%) Ex-IVDA, n (%) Alcohol, consumer n(%) Alcohol (SDU), median, IQR | 10 (58.8) 2.7 (0–22) 2 (11.8) 0 6 (35.3) 0 (0-1.5) | 43 (38.9) 1.1 (0–12) 20 (18.5) 1 (0.9) 57 (52.8) 0.2 (0–1) | 0.12 0.267 0.497 1 0.18 0.397 | |
Duration of HIV; mean (IQR) | 90(52.5-214.5) | 61.5 (29.25–123.5) | 0.138 | |
CD4 mean nadir; cells/µL (± SD) | 299.59(261.1) | 341.4 (205.9) | 0.456 | |
Naïve | 1 (5.9) | 9 (8.3) | 1 | |
VL of HIV, log10(± SD) VL < 50 copies/mL, n (%) | 2.54(3.12) 15 (88.2) | 3.79(4.51) 87 (80.6) | 0.469 0.736 | |
CD4 mean; cells/µL, (± SD) | 696.92(215) | 729.01(268.4) | 0.64 | |
CD8 mean; cells/µL (± SD) CD4/CD8 | 1038.4(273.4) 0.74 (0.29) | 995.6(446) 1.4 (5.85) | 0.71 0.634 | |
Previous AIDS diagnosis; n (%) | 8 (47.1) | 31 (28.7) | 0.129 | |
Median duration of ART; months (IQR) | 51 (26.5–74) | 55 (23–111) | 0.214 | |
Virological failure, n (%) | 0 | 4(4) | 0.418 | |
Syphilis, n (%) Other STD, n (%) | 4 (23.5) | 22 (20.4) | 0.753 | |
HCV, n (%) | 0 | 3 | 1 | |
HBV, n (%) | 0 | 2 (1.9) | 1 | |
AIN1 (1st HRA), n(%) | 9 (52.9) | 57 (52.8) | 0.99 | |
HR-HPV baseline, n (%) | 13 (76.5) | 74 (73.3) | 1 | |
LR-HPV baseline, n (%) | 11 (64.7) | 59 (58.4) | 0.625 | |
HR and LR-HPV baseline, n(%) | 10 (58.8) | 47 (46.5) | 0.35 | |
HPV at baseline visit HPV-6, n (%) HPV-11, n (%) HPV-16, n (%) HPV-18, n (%) HPV-31, n (%) HPV-33, n (%) HPV-35, n (%) HPV-39, n (%) HPV-45, n (%) HPV-51, n (%) HPV-53, n (%) HPV-56, n (%) HPV-58, n (%) HPV-59, n (%) HPV-66, n (%) HPV-68, n (%) HPV-73, n (%) HPV-82, n (%) | 3 (17.6) 3 (17.6) 5 (29.4) 1 (5.9) 2(11.8%) 1 (5.9) 0 (0) 1 (5.9) 2 (11.8) 2 (11.8) 0 (0) 1 (5.9) 1 (5.9) 3 (17.6) 1 (5.9) 0 4 (23.5) 0 | 16 (15.8) 12 (11.9) 24 (23.8) 7 (6.9) 16 (15.8) 11(10.9) 11 (10.9) 5 (5) 12 (11.9) 13 (12.9) 10 (9.9) 6 (5.9) 7 (6.9) 16 (15.8) 13 (12.9) 11 (10.9) 11 (10.9) 6 (5.9) | 1 0.452 0.761 1 1 1 0.362 1 1 1 0.354 1 1 1 0.689 0.362 0.228 0.591 | |
HPV 12 months after first dose HPV-6, n (%) HPV-11, n (%) HPV-16, n (%) HPV-18, n (%) HPV-31, n (%) HPV-33, n (%) HPV-35, n (%) HPV-39, n (%) HPV-45, n (%) HPV-51, n (%) HPV-53, n (%) HPV-56, n (%) HPV-58, n (%) HPV-59, n (%) HPV-66, n (%) HPV-68, n (%) HPV-73, n (%) HPV-82, n (%) | 4 (23.5) 2 (11.8) 7 (41.2) 5 (29.4) 1 (5.9) 2 (11.8) 1 (5.9) 0 2 (11.8) 0 1 (5.9) 2 (11.8) 0 3 (17.6) 3 (17.6) 2 (11.8) 1 (5.9) 0 | 22 (22.4) 13 (13.3) 37 (37.8) 11 (11.2) 16 (16.3) 6 (6.1) 8 (8.2) 8 (8.2) 11 (11.2) 13 (13.3) 13 (13.3) 9 (9.2) 9 (9.2) 10 (10.2) 6 (6.2) 9 (9.2) 4 (4.1) 5 (5.2) | 1 1 0.789 0.06 0.461 0.336 1 0.266 1 0.211 0.690 0.665 0.365 0.405 0.131 0.665 0.558 1 | |
P*: p-value; p < 0.05 |
q-HPV vaccine: quadrivalent human papillomavirus vaccine; Ab q-HPV Vaccine: antibody to q-HPV vaccine. HRA: high resolution anoscopy. SDU: standard drink unit. |