Persistence of neutralizing antibody and its protective efficacy induced by a live attenuated tetravalent dengue vaccine, KD-382, in cynomolgus monkeys.

An effective dengue vaccine should induce a long-lasting immune response against all four serotypes simultaneously with a minimum number of immunizations. Our live attenuated tetravalent dengue vaccine candidate, KD-382, was developed using a classical host range mutation strategy (no addition of artificial genetic modification). In our previous study, cynomolgus monkeys immunized with a single dose of KD-382 seroconverted to all four serotypes. However, it is important to determine if neutralizing antibodies (NAbs) induced by KD-382 can work as a long-lasting immune response to prevent dengue. In this study, a single dose of KD-382 induced a strong NAb response against all four serotypes in cynomolgus monkeys. We also confirmed that NAb titers against all four serotypes persist for at least five years, indicating its high potential as a dengue vaccine candidate. Next, we evaluated the effect of pre-existing dengue immunity on NAb responses induced by KD-382. We administered KD-382 to cynomolgus monkeys pre-administered one of the monovalent parental wild-type strains 60 days before vaccination. Regardless of the pre-immunized serotype, all the monkeys showed sufficient tetravalent NAb responses, which lasted for over two years. All the KD-382 vaccinated monkeys were then challenged with different parental wild-type viruses than that used for pre-administration; viral RNA in the serum was less than the lower limit of quantification, indicating complete protection against secondary heterologous dengue infection without any harmful disease enhancement. Consequently, KD-382 successfully induced a long-lasting and protective tetravalent NAb response in monkeys, suggesting that KD-382 is a promising vaccine candidate usable for both dengue seronegative and seropositive individuals.

Well-balanced immune response and protective efficacy induced by a single dose of live attenuated tetravalent dengue vaccine (KD-382) in monkeys.

One of the challenges developing a live attenuated tetravalent dengue vaccine (TDV) is to overcome the presumed viral interference that may be preventing the induction of a balanced immune response to all 4 serotypes of the dengue virus (DENV1-4). Our live attenuated TDV candidate was developed from wild-type (wt) parental strains (DENV1/03135, DENV2/99345, DENV3/16562, and DENV4/1036, respectively) using a classical host range mutation strategy: the same strategy used for the approved live attenuated smallpox, polio, and MMR vaccines. Our vaccine candidate is expected to mimic natural dengue virus infection, as it provides all the components of dengue virus, including both structural and nonstructural proteins. Therefore, induction of more solid and comprehensive immune responses against pathogenic dengue viruses is also expected. In this study, we evaluated the neutralizing antibody responses for each serotype induced by a single subcutaneous administration of 6 formulations, which were composed of different combinations of vaccine strains and were all of different dosages. These formulations were tested in dengue-naïve cynomolgus macaques. As a result, regardless of the TDV formulation, all the monkeys immunized with TDVs seroconverted to all the 4 serotypes at day 30. Next, we evaluated protection ability of the selected formulations of TDV candidate, no RNAemia was detected from any of the immunized monkeys upon s.c. challenge with wtDENV. The findings of this non-human primate study indicate that our vaccine candidate is very promising; it can be further evaluated for safety and efficacy in human clinical studies.

Profiling of the antibody response to attenuated LC16m8 smallpox vaccine using protein array analysis.

Concerns about bioterrorism and outbreaks of zoonotic orthopoxvirus require safe and efficacious smallpox vaccines. We previously reported the clinical efficacy and safety profiles of LC16m8, a live, attenuated, cell culture-derived, smallpox vaccine, examined in over 3000 healthy Japanese adults with various vaccination histories. In this study, serum of approximately 200 subjects pre and post LC16m8 vaccination were subjected to a vaccinia virus-specific protein array to evaluate the proteome-wide immunogenicity. The relationships between antigen-specific antibodies and plaque reduction neutralization titers were analyzed. LC16m8 induced antibodies to multiple vaccinia antigens in primary-vaccinated individuals and yielded effective booster responses in previously vaccinated individuals, demonstrating similar antibody profiles to those reported for other vaccinia virus strains. Several immunodominant antigens were indicated to be important for neutralization of the intracellular mature virion. The similarity of antibody profiles between LC16m8 and other smallpox vaccine strains supports the immunogenicity and protective efficacy of LC16m8.

12-Week Effectiveness and Safety of Low-Density Lipoprotein Cholesterol-Lowering Therapy by Proprotein Convertase Subtilisin/Kexin Type 9 Inhibition in Patients With Familial Hypercholesterolemia and Hypercholesterolemia　- Data From a Real-World Observational Study of Evolocumab in Japan.

Background: Evolocumab is the first monoclonal antibody against proprotein convertase subtilisin/kexin type 9 (PCSK9) approved in Japan for the treatment of patients with familial hypercholesterolemia (FH) and hypercholesterolemia (HC). This study assessed the 12-week effectiveness and safety of low-density lipoprotein cholesterol (LDL-C)-lowering therapy by PCSK9 inhibition in patients with FH (homozygous [HoFH] or heterozygous [HeFH]) and HC by analyzing evolocumab data collected in the real-world setting in Japan. Methods and Results: Overall, 427 patients (mean±SD age, 61.6±13.8 years; female, 38.4%; 28 HoFH, 320 HeFH, 79 HC), enrolled from 299 clinical sites, were included in the safety analysis set. The major cardiovascular risk factors were coronary artery disease (77.3%), diabetes mellitus/impaired glucose tolerance (38.6%), and hypertension (65.1%). Median follow-up duration was 85.0 days. After 12 weeks of evolocumab treatment, the mean±SD percent change from baseline in LDL-C was -45.5%±27.0% (n=23) in HoFH (P<0.001 vs. baseline; t-test), -54.2%±29.0% (n=280) in HeFH (P<0.001), and -64.6%±22.4% (n=72) in HC (P<0.001) patients. The incidence of adverse drug reactions was 5.4% (23/427). Conclusions: Results suggest that patients receiving evolocumab treatment in the real-world setting were predominantly those with FH and HC in the secondary prevention group. LDL-C-lowering effectiveness with evolocumab was observed in FH (both HoFH and HeFH) and HC patients.

Safety and efficacy of adalimumab treatment in Japanese patients with psoriasis: Results of SALSA study.

The safety and efficacy of adalimumab were evaluated over 24 weeks in Japanese patients with psoriasis in routine clinical practice. In this multicenter, observational, open-label, postmarketing study, primary efficacy measures included the Psoriasis Area and Severity Index (PASI) and the Dermatology Life Quality Index (DLQI) in all patients with psoriasis. In patients with psoriatic arthritis (PsA), the 28-joint Disease Activity Score (DAS28) and the visual analog scale (VAS) pain were also evaluated. Safety was assessed based on the frequency of adverse drug reactions (ADR). Among patients with psoriasis evaluated for efficacy (n = 604), significant improvements from baseline were observed in mean PASI and DLQI scores at weeks 16 and 24 (all P < 0.0001). Furthermore, in psoriasis patients without PsA, the PASI 75/90 response rates were 55.9%/28.4% at week 16 (n = 306) and 65.6%/43.3% at week 24 (n = 270), respectively. In patients with PsA evaluable for effectiveness, significant improvements from baseline were observed in PASI, DAS28 erythrocyte sedimentation rate, DAS28 C-reactive protein and VAS pain at weeks 16 and 24 (all P < 0.0001). ADR and serious ADR were reported by 26.1% and 3.3%, respectively, of 731 safety evaluable patients with psoriasis; no unexpected safety findings were noted. The safety profile and effectiveness of adalimumab for the treatment of psoriasis in a routine clinical setting were as expected in Japanese patients.

Safety of Adalimumab and Predictors of Adverse Events in 1693 Japanese Patients with Crohn's Disease.

BACKGROUND AND AIMS: Data from an all-cases post-marketing study were used to evaluate the safety and effectiveness of adalimumab in Japanese patients with Crohn's disease [CD]. METHODS: Patients received adalimumab for 24 weeks. Data from all patients [n = 1693] were used for the safety assessment. Data from patients with CD activity index [CDAI] ≥ 150 at baseline were used for the effectiveness assessment. RESULTS: The most frequent serious adverse drug reaction [ADR] was infection and infestations [6.6 events/100 patient-years]. The risk of serious infections increased in patients who had a history of malignancy and those with concomitant corticosteroid use. Of 415 patients who had switched from another anti-tumour necrosis factor alpha [TNFα] agent to adalimumab due to ADRs, 7.2% discontinued due to ADRs to adalimumab. Ten of 13 patients with a history of tuberculosis [TB] received prophylactic medication, and none developed TB. TB developed in one patient with no history of TB or anti-TB prophylaxis. Remission rates were 41.3% and 32.4% at 4 and 24 weeks, respectively. Remission rates did not differ between patients with and without concomitant use of immunomodulators. Predictive variables for increased effectiveness were CDAI ≤ 220 and disease duration of ≤ 2 years. Perianal lesions and loss of response to previous anti-TNFα agents affected effectiveness. CONCLUSIONS: The most frequent serious ADR was infection. Adalimumab significantly reduced disease activity, without any unexpected ADRs. Development of active TB during adalimumab therapy can be prevented through TB screening and prophylaxis. In patients who switched from another anti-TNFα agent to adalimumab due to ADRs, adalimumab was well tolerated.

Freeze-dried live attenuated smallpox vaccine prepared in cell culture "LC16-KAKETSUKEN": Post-marketing surveillance study on safety and efficacy compliant with Good Clinical Practice.

BACKGROUND: In Japan, production of smallpox vaccine LC16m8 (named LC16-KAKETSUKEN) was restarted and was determined to be maintained as a national stockpile in March 2002. OBJECTIVE: To conduct a post-marketing surveillance study of the vaccination of freeze-dried live attenuated smallpox vaccine prepared in cell culture LC16-KAKETSUKEN using attenuated vaccinia strain LC16m8. The study complied with Good Clinical Practice, focusing on a comparison between primary vaccinees and re-vaccinees. METHOD: 268 personnel (261 males and 7 females) of the Japan Ground Self-Defense Force were inoculated with LC16-KAKETSUKEN and thereafter adverse events and efficacy were evaluated. RESULTS: Among 268 vaccinee participants, the following vaccinees showed adverse events, none serious: 53 of 196 primary vaccinees (without previous smallpox vaccination), 4 of 71 re-vaccinees (with previous smallpox vaccination) and 1 vaccinee with unknown previous vaccination history. A breakdown of adverse events observed in this study (total 268 vaccinees) showed the following minor or mild adverse events: 52 (19.4%) swelling of axillary lymph node, 4 (1.5%) fever, 2 (0.7%) fatigue, 1 (0.4%) of rash, 14 (5.2%) erythema at the inoculation site, 1 (0.4%) swelling at the inoculation site and 1 (0.4%) autoinoculation. The incidence of adverse events for primary vaccinees (53/196; 27.0%) was significantly higher than for re-vaccinees (4/71; 5.6%). However, the proportion of vaccine take was significantly higher for primary vaccinees (185/196; 94.4%) than for re-vaccinees (58/71; 81.7%). Although the proportion of vaccine take of re-vaccinees was significantly lower than for primary vaccinees due to preexisting immunity by previous vaccination, no significant difference was found in neutralizing antibody titers between primary vaccinees and re-vaccinees at 1, 4 and 7 months after LC16-KAKETSUKEN vaccination. CONCLUSION: The present post-marketing surveillance study compliant with Good Clinical Practice demonstrated the efficacy and safety of the smallpox vaccine LC16-KAKETSUKEN in an adult population. LC16-KAKETSUKEN is the sole currently available licensed smallpox vaccine for both adult and pediatric populations.

Vaccinia virus strain LC16m8 defective in the B5R gene keeps strong protection comparable to its parental strain Lister in immunodeficient mice.

BACKGROUND: Attenuated vaccinia virus strain, LC16m8, defective in the B5R envelope protein gene, is used as a stockpile smallpox vaccine strain in Japan against bioterrorism: the defect in the B5R gene mainly contributes to its highly attenuated properties. METHODS: The protective activity of LC16m8 vaccine against challenge with a lethal dose of vaccinia Western Reserve strain was assessed in wild-type and immunodeficient mice lacking CD4, MHC class I, MHC class II or MHC class I and II antigens. RESULTS: The immunization with LC16m8 induced strong protective activity comparable to that of its parent strain, Lister (Elstree) strain, in wild-type mice from 2 days to 1 year after vaccination, as well as in immunodeficient mice at 2 or 3 weeks after vaccination. These results implicated that the defect in the B5R gene hardly affected the potential activity of LC16m8 to induce innate, cell-mediated and humoral immunity, and that LC16m8 could be effective in immunodeficient patients. CONCLUSION: LC16m8 with truncated B5 protein has an activity to induce immunity, such as innate immunity and subsequent cell-mediated and humoral immunity almost completely comparable to the activity of its parental strain Lister.

Trend of patient characteristics and its impact on the response to adalimumab in patients with rheumatoid arthritis: post hoc time-course analysis of an all-case PMS in Japan.

OBJECTIVES: To investigate the relationship between changes in patient characteristics over time and the effectiveness and safety of adalimumab in the treatment of rheumatoid arthritis (RA) in clinical practice. METHODS: Patients enrolled in the post-marketing registry study in Japan were divided into 5 subgroups based on the time adalimumab treatment was initiated. Demographic and baseline characteristics and responses to adalimumab were compared among the 5 subgroups to detect any time-course trend. Multiple logistic regression analysis was performed to identify characteristics that were significantly associated with the effectiveness or safety of adalimumab and to estimate response rates and the incidence of adverse drug reactions in individual subgroups. RESULTS: During the study period, patient characteristics changed significantly over time, in particular with regard to prior biologic use and concomitant methotrexate therapy. There was a significant trend toward higher response rates and lower incidence of infections and injection-site reactions in patients initiating adalimumab later in the study. Patient characteristics, such as concomitant methotrexate therapy and early stage RA, were significant predictors of the effectiveness and safety of adalimumab. CONCLUSIONS: Patient characteristics have changed since adalimumab became available for the treatment of RA; several of these characteristics were significant predictors of adalimumab effectiveness and safety.

Safety of attenuated smallpox vaccine LC16m8 in immunodeficient mice.

Freeze-dried live attenuated smallpox vaccine LC16m8 prepared in cell culture has been the sole smallpox vaccine licensed in Japan since 1975 and was recently recommended as a WHO stockpile vaccine. We evaluated the safety of recently remanufactured lots of LC16m8 using a series of immunodeficient mouse models. These models included suckling mice, severe combined immunodeficiency disease (SCID) mice, and wild-type mice treated with cyclosporine. LC16m8 showed extremely low virulence in each of the three mouse models compared with that of its parental strains, Lister and LC16mO. These results provide further evidence that LC16m8 is one of the safest replication-competent smallpox vaccines in the world and may be considered for use in immunodeficient patients.

Smallpox vaccine safety is dependent on T cells and not B cells.

The licensed smallpox vaccine, ACAM2000, is a cell culture derivative of Dryvax. Both ACAM2000 and Dryvax are administered by skin scarification and can cause progressive vaccinia, with skin lesions that disseminate to distal sites. We have investigated the immunologic basis of the containment of vaccinia in the skin with the goal to identify safer vaccines for smallpox. Macaques were depleted systemically of T or B cells and vaccinated with either Dryvax or an attenuated vaccinia vaccine, LC16m8. B cell depletion did not affect the size of skin lesions induced by either vaccine. However, while depletion of both CD4(+) and CD8(+) T cells had no adverse effects on LC16m8-vaccinated animals, it caused progressive vaccinia in macaques immunized with Dryvax. As both Dryvax and LC16m8 vaccines protect healthy macaques from a lethal monkeypox intravenous challenge, our data identify LC16m8 as a safer and effective alternative to ACAM2000 and Dryvax vaccines for immunocompromised individuals.