Forty-seven JDM patients and 41 HC were initially eligible for the study. Four JDM patients and two participants from the HC group had previously received one dose of the vaccine. One JDM patient had received two doses. During the study period, five patients did not receive all three doses of the vaccine: three due to lack of follow-up, one patient due to fear of AEFV, and the last patient became pregnant after receiving two doses. Forty-two JDM patients and 35 HC completed the 3-dose schedule. The flow diagram describing the administration of the qHPV vaccine doses prior to and during the study is presented in figure 1.
Characteristics of the participants at study inclusion are summarized in table 1. Median age at diagnosis of JDM was seven years. Median age at first dose of qHPV vaccine was 16 for JDM patients and 14 for HC. Twelve/47 (25.5%) patients had inactive disease at study inclusion and were not using any immunosuppressive medication (JDM group A). Thirty-five/47 (74.5%) JDM patients used at least one medication for disease control at study inclusion, divided between 17/47 (36.2%) patients with inactive disease (JDM group B) and 18/47 (38.3%) with active disease despite the use of immunosuppressive medications (JDM group C). Nine/47 (19.1%) JDM patients and 11/47 (26.8%) HC reported having initiated sexual activity before their inclusion in the study. Baseline blood samples were collected from 37 JDM patients and 39 HC. Baseline samples were not taken from the participants who had been vaccinated before the study. At baseline, two/39 (5%) HC were seropositive for HPV16 and one/39 (3%) for HPV18. Seropositivity at baseline for JDM patients was 10/37 (27%) for HPV16, and 9/37 (24%) for HPV18. Of the 13 patients who were seropositive for HPV 16 and/or HPV18 at baseline, only two reported being sexually active at the time of the study.
Concerning AEFV evaluation, a total of 121 diaries (40 after the first dose, 41 after the second dose, and 40 after the third dose) from 47 JDM patients were analyzed, as well as 111 diaries (38 after the first and second doses and 35 after the third dose) from 41 HC individuals. Pain was the most common local adverse event reported for both JDM patients (55%) and HC (60.5%) after the first dose (p = 0.653). After the third dose, despite the decrease in frequency, local pain remained the most common local symptom reported by 40% of the JDM group and 54.3% of the HC (p = 0.252). The frequency of all other local symptoms was similar between both groups, except for bruise and edema, which were more frequent among the HC group after receiving the third vaccine dose (p = 0.019 and p = 0.010, respectively). Headache was the most frequently reported systemic adverse event after all three HPV doses among patients and HC (p 0.534), followed by fatigue (p = 0.263). JDM patients presented significantly more nausea after the first dose (p = 0.014) and more itchiness after the third dose (p = 0.013) than HC. No severe adverse events were related to the vaccination. The majority of AEFV lasted only one or two days and almost none more than seven days. The occurrence of AEFV and related statistical analysis are described in table 2.
In total, JDM patients had 42 baseline visits, 42 visits after the second dose, 40 visits after the third dose, and 26 visits six months after the third dose. Table 3 shows the muscular and cutaneous disease activity evaluation and the medication in use by JDM patients at each study visit. All JDM patients were evaluated by the CMAS score, whereas the MMT score was performed only by a few investigators. Consequently, the CMAS was the main score for muscular evaluation in this study. The median of disease activity measured through the CMAS score for the JDM population was 50 at the first visit, 51.5 at the second visit, and 50 at the third and fourth visits. The analysis of disease activity among the JDM groups A, B, and C revealed a median CMAS of 52 for groups A and B at the four visits, whereas group C presented a median CMAS of 37, 42, 46, and 43 at the four visits, respectively. Five patients from group C (27.8% patients from this group) demonstrated an improvement greater than 20% in their CMAS (CMAS scores increased 15 to 20 points in these five patients right after the third dose compared with baseline). The analysis of disease activity performed six months after the end of the 3-dose schedule showed that two of the five patients, who had significantly improved, presented worsening scores in comparison with the scores presented immediately after receiving the third dose. One of these had a CMAS score of 48 after the third dose. Due to her excellent improvement, one of her medications was suspended (cyclosporin). Unfortunately, at the last visit she had returned to her baseline score (CMAS 28). The other patient also scored CMAS 48 after receiving the third dose, however at the final visit ended with only two extra points compared to baseline (final CMAS 31). One patient from group B presented worsening in scores of greater than 20% in the fourth visit and maintained a final score lower than her baseline score (CMAS at first, second, and third visits: 48; CMAS at fourth visit: 32). This patient had her only medication (cyclosporin) suspended during the study. The changes in CMAS are presented in table 4. There was no significant worsening regarding cutaneous manifestation between the baseline and after the third vaccine dose (p = 0.074 for rash; p = 0.814 for Gottron’s papules; p = 0.479 for heliotrope).
Twelve/42 (28.6%) patients presented at least one typical cutaneous manifestation at baseline. Nine/42 (21.4%) had a cutaneous rash, 12/42 (28.6%) had Gottron’s papules, and seven/42 (16.7%) had heliotrope of the upper eyelids. Regarding the patients that had already presented a cutaneous abnormality at baseline, improvement in the lesion occurred in five/nine (55.5%) patients with cutaneous rash, three/12 (25%) with Gottron’s papules, and three/seven (37.5%) with heliotrope, after receiving three doses of the vaccine. Worsening occurred in one/nine (11.1%) patients with a rash and two/seven (28.6%) patients with heliotrope. Only one patient from group B had new-onset JDM cutaneous manifestations during the study. The changes in cutaneous manifestations are demonstrated in table 4. There were no differences regarding cutaneous activity between the baseline and after receiving the third vaccine dose (p > 0.050 for all evaluated cutaneous manifestations).
Corticosteroids were the most commonly prescribed medication, used by 20/42 (47.6) of the JDM patients at baseline, with a median dose of 15 mg/day. Of the 20 patients who used corticosteroids, 15 were from group C (100% of the group) and five from group B (31.3% of the group). Hydroxychloroquine was the second most commonly prescribed medication, used by 17/42 (40.5%) of the patients at baseline, followed by methotrexate (35.7%), azathioprine (19%), and cyclosporine (16.7%). Two patients were using human immunoglobulin (IGIV) (4.8%). One patient was using mycophenolate mofetil, and one patient was using cyclophosphamide at baseline (2.4% each). Regarding the use of cyclophosphamide, two patients had recently used it before inclusion in the study (received the last dose six and eight months before inclusion). These two patients belonged to group C.
Throughout the study, 27/40 patients (67.5%) maintained the same (stable) treatment. No patients from group A used any medication during the study period. Six/40 (15%) patients had their immunosuppressive treatment increased due to disease activity. One patient from group B started prednisone 15mg/day after receiving three vaccine doses, due to cutaneous activity (her CMAS was 52 throughout the study). This patient’s prednisone dose was decreased to 5mg/day at the last visit. Five patients from group C (27.8% of the group) had their immunosuppressive medication changed or had to initiate a new medication during the study, associated with an increase in the prednisone dose. However, these five patients already had active disease before receiving the initial qHPV dose (CMAS of these five JDM patients was between 37 and 46 at baseline). In three of these patients, the prednisone dose was decreased at the next study visit and one of them had IGIV suspended. Fourteen/40 (35%) patients had their immunosuppressive treatment decreased during the study. Three patients from group B and four patients from group C had one or two immunosuppressive medications withdrawn (three and four patients, respectively). Among the medications removed were prednisone (two patients), cyclophosphamide (one patient), and IGIV (one patient). In addition to these two patients who had prednisone withdrawn, the prednisone dose of nine more patients was decreased during the study. The main changes in the medications used by the patients are shown in table 4. No statistical significance was found between the baseline and the visit after the third vaccine dose regarding drug therapy of the JDM patients (p = 1.000).
Thirty-six JDM patients received the first two doses of qHPV vaccine and had a blood sample collected after it. After the second dose, the seropositivity was 94% and 92% for HPV16 and HPV18, respectively. Two patients remained seronegative for both HPV types (one from group B and one from group C), and one patient remained seronegative for only HPV18 (group C). The patient from group B was using only methotrexate 25mg/week. The patient from group C that remained seronegative for both HPV types was using prednisone 10mg/day plus hydroxychloroquine. The patient that remained seronegative only for HPV18 was under a low dose of prednisone (7,5mg/day) associated with hydroxychloroquine and azathioprine. The patient that was using cyclophosphamide during the study and the two patients who had recently used this medication demonstrated seropositivity for both HPV serotypes. The comparative analysis of the serological response after two doses of the vaccine did not demonstrate differences between the JDM groups A, B, and C (p = 1.000 for HPV16 and p = 0.770 for HPV18).
Seropositivity of the 31 JDM patients who completed the 3-dose schedule and had a blood sample collected after it was 100% for HPV16 and 97% for HPV18. Only one JDM patient remained seronegative for HPV18 immediately after receiving all three doses. This was the same patient who had already remained seronegative only for HPV18 after receiving two doses (group C). There were no differences between JDM groups A, B, and C regarding the comparative analysis of the serological response after three doses of the vaccine (p = 1.000 for both HPV types).
Blood samples were available for 17 JDM patients six months after the final dose. This analysis showed that 94% of the patients remained seropositive for HPV16 and HPV18. Only one patient, who had presented seropositive for HPV16 and 18 during the study, became seronegative for both HPV types during the following months. This patient had inactive disease and was only using cyclosporine during the study period (group B). Once more, JDM groups A, B, and C showed similar serological response to the vaccine (p = 1.000 for both HPV types).
The HC group responded to the vaccination after two and three doses, with 100% seropositivity for both HPV serotypes (samples available from 14 HC after two doses, and from 31 after three doses). No differences were observed in the comparative analysis of the serological response to vaccination between JDM patients and HC, either after two doses (p = 1.000 for HPV16 and p = 0.265 for HPV18), or after three doses (p = 1.000 for both HPV types). The serological analysis of JDM patients and HC is shown in table 5. Samples were not collected from the HC group six months after the last dose.