scholarly journals Ustekinumab trough concentration affects clinical and endoscopic outcomes in patients with refractory Crohn’s disease: a Chinese real-world study

2021 ◽  
Vol 21 (1) ◽  
Author(s):  
Jia-yin Yao ◽  
Min Zhang ◽  
Wei Wang ◽  
Xiang Peng ◽  
Jun-zhang Zhao ◽  
...  

Abstract Background Ustekinumab (UST), a newly-used biologic targeting p40 subunit of IL12 and IL23 in China, exerts a confirmed therapeutic effect on the induction and maintenance therapies for refractory Crohn’s disease (CD). Therapeutic drug monitoring based on trough and antibody concentration is of core importance when treating patients who lose response to UST. We aimed to analyze the UST exposure–response relationship in CD treatment in the real-world setting. Methods We retrospectively enrolled patients with CD who received UST between March 1, 2020 and May 31, 2021, at the inflammatory bowel disease (IBD) center of the Sun Yat-Sun Affiliated Sixth Hospital. Baseline characteristic information, biomarker examination, clinical outcomes determined by the Crohn’s disease activity index (CDAI), and endoscopic outcomes evaluated using a simple endoscopic score for Crohn’s disease (SES-CD) at week 16/20 were collected. The optimal UST cut-off trough concentration was identified using receiver operating characteristic curve (ROC) analysis. Results Nineteen eligible patients were included in the study, the mean age was 29.1 ± 9.1 years and the mean disease duration was 5.5 ± 4.7 years. At the initiation of the study, 89.5% of the patients had been exposed to prior biologics, 42.1% had previous CD-related surgeries, and 52.6% had perianal diseases. At week 16/20 after the UST initiation, clinical response, clinical remission, endoscopic response, and endoscopic remission were 89.5%, 84.2%, 42.2%, and 73.7%, respectively. The cut-off optimal trough concentration for UST was 1.12 μg/mL, as determined by the ROC with an area under the curve (AUC) of 0.78, sensitivity of 87.5%, and specificity of 72.7%. Patients with a UST trough concentration > 1.12 μg/mL had a significantly higher rate of endoscopic remission than those without (70.0% vs. 11.1%, P = 0.02). Conclusions UST is an effective therapeutic option for refractory CD treatment. A UST trough concentration above 1.12 μg/mL was associated with endoscopic remission at week 16/20 after UST initiation. Trial registration This study was approved and retrospectively registered by the Ethics Committee of Sun Yat-Sen University (2021ZSLYEC-066, March 29, 2021) and the Clinical Trial Registry (NCT04923100, June 10, 2021).

Author(s):  
Neeraj Narula ◽  
Emily C L Wong ◽  
Parambir S Dulai ◽  
John K Marshall ◽  
Jean-Frederic Colombel ◽  
...  

Abstract Background and Aims There is paucity of evidence on the reversibility of Crohn’s disease [CD]-related strictures treated with therapies. We aimed to describe the clinical and endoscopic outcomes of CD patients with non-passable strictures. Methods This was a post-hoc analysis of three large CD clinical trial programmes examining outcomes with infliximab, ustekinumab, and azathioprine, which included data on 576 patients including 105 with non-passable strictures and 45 with passable strictures, as measured using the Simple Endoscopic Score for Crohn’s Disease [SES-CD]. The impact of non-passable strictures on achieving clinical remission [CR] and endoscopic remission [ER] was assessed using multivariate logistic regression models. CR was defined as a Crohn’s Disease Activity Index [CDAI] <150, clinical response as a CDAI reduction of ≥100 points, and ER as SES-CD score <3. Results After 1 year of treatment, patients with non-passable strictures demonstrated the ability to achieve passable or no strictures in 62.5% of cases, with 52.4% and 37.5% attaining CR and ER, respectively. However, patients with non-passable strictures at baseline were less likely to demonstrate symptom improvement compared with those with passable or no strictures, with reduced odds of 1-year CR (adjusted odds ratio [aOR] 0.17, 95% CI 0.03–0.99, p = 0.048). No significant differences were observed between patients with non-passable strictures at baseline and those with passable or no strictures in rates of ER [aOR 0.82, 95% CI 0.23–2.85, p = 0.751] at 1 year. Conclusions Patients with non-passable strictures can achieve symptomatic and endoscopic remission when receiving therapies used to treat CD, although they are less likely to obtain CR compared with patients without non-passable strictures. These findings support the importance of balancing the presence of non-passable strictures in trial arms.


2020 ◽  
Vol 26 (Supplement_1) ◽  
pp. S75-S75
Author(s):  
Scott D Lee ◽  
Anand Singla ◽  
Caitlin Kerwin ◽  
Kindra Clark-Snustad

Abstract Background Vedolizumab (VDZ) is an effective treatment for Crohn’s disease (CD); however, inadequate and loss of response is common. Pivotal VDZ trials evaluated alternative dosing intervals, demonstrating numeric but not statistical superiority in efficacy as compared to FDA-approved dosing. The safety and effectiveness of FDA-approved and modified-dosing schedules in a real-world population are unknown. We aimed to evaluate clinical and endoscopic effectiveness & safety of standard and modified maintenance VDZ dosing in a real world cohort. Methods We retrospectively reviewed CD patients (pts) treated with >3 months VDZ, assessing Harvey Bradshaw Index (HBI), Simple Endoscopic Score for Crohn’s disease (SESCD), Short Inflammatory Bowel Disease Questionnaire (SIBDQ), C-reactive protein (CRP), albumin and hematocrit prior to and following standard VDZ dosing, and prior to and following modified VDZ maintenance dosing. We measured duration on therapy and adverse events. Results We identified 226 eligible pts, mean age 41.5 years, 55.3% female, median disease duration 10 years, 88.9% with prior biologic exposure. Mean duration on VDZ was 28.3 months. Standard VDZ dosing: 61.5% of pts with active clinical disease and adequate follow up data achieved clinical response after 3–12 months; 41.0% had clinical remission. 51.9% of pts with active endoscopic disease and adequate follow up data achieved mucosal improvement; 42.3% had endoscopic remission; 26.0% had mucosal healing after 3–24 months. 50.0% of pts with elevated CRP and adequate follow up data normalized CRP after 3–12 months. Modified maintenance dosing: 72 non-remitters to standard VDZ dosing received modified VDZ maintenance dosing. 51.5% of pts with active clinical disease prior to starting dose modification and adequate follow up data achieved clinical response after 3–12 months of modified maintenance dosing; 42.4% had clinical remission. 22.2% of pts with SESCD ≥3 prior to starting dose modification achieved mucosal improvement after 3–24 months; 22.2% had mucosal healing. 26.7% of pts with SESCD ≥4 prior to starting modified dosing had endoscopic remission after 3–24 months. 50.0% of pts with elevated CRP and adequate follow up data normalized their CRP after 3–12 months. Safety: 82.7% of pts reported ≥1 adverse events, most commonly infection and worsening CD symptoms. Discussion Standard VDZ dosing resulted in clinical and endoscopic improvement in pts with moderate-severe CD, with prior exposure to multiple advanced therapies. For non-remitters to standard dosing, modified VDZ maintenance dosing improved clinical disease activity in ∼50% of pts and improved endoscopic disease activity in ∼20% of pts, suggesting that for pts who did not achieve remission with standard VDZ dosing, modified VDZ dosing may result in clinical and endoscopic improvement.


2020 ◽  
Vol 14 (Supplement_1) ◽  
pp. S331-S333
Author(s):  
C Liefferinckx ◽  
M Fassin ◽  
D Thomas ◽  
C Minsart ◽  
A Cremer ◽  
...  

Abstract Background Therapeutic drug monitoring (TDM) is a diagnostic tool in the monitoring of anti-TNF therapies. Yet, the benefit for TDM of new biologics such as ustekinumab (USK) is still controversial in real-world experiences. Methods This monocentric retrospective study aims to correlate USK trough levels (TLs) with clinical and endoscopic data. All patients have given written consent to the Biobank (B2011/005). Endoscopic disease was defined as quiescent in absence of endoscopic lesions, mild disease in presence of few superficial ulcerations, moderate in presence of several ulcers and severe in presence of numerous deep ulcers and/or inflammatory stenosis. 313 serum USK samples from 67 Crohn’s disease patients were used to measure USK TL (USK ELISA, apDia) while 88 samples (at week 16, and before and after optimisation) were used to measure anti-drug antibody (ADA), using a drug-tolerant affinity capture elution anti-ustekinumab assay Results Demographic and baseline data of our population are presented in Table 1. The median follow-up was 73 weeks (IQR 39–92). An optimisation due to loss of response was required in 44.8% of patients (n = 30) after a median time of 38 weeks (IQR 24–55). To evaluate the drug efficacy, an endoscopy was performed in 61% of cases at a median time of 35 weeks (IQR 27–47). TLs were 5.2 µg/ml (IQR 2.1–8.8), 1.7 µg/ml (IQR 0.3–4.3) and 2.6 µg/ml (IQR 0.6–4.1) at week 8, 16 and 24, respectively. TLs at week 8 were correlated to the induction IV dose administrated (r = 0.3, p = 0.03). At week 16, low TLs were associated with higher endoscopic activity in the follow-up (p = 0.02), although this was not the case at week 8 (p = 0.5) (Figure 1). Patients not requiring an optimisation had higher TLs in maintenance than patients requiring optimisation (2.45 µg/ml (IQR 1.3–4.4) vs. 1.15 µg/ml (IQR 0.1–2.24), p = 0.008). Obviously, optimisation significantly increased TLs (1.15 µg/ml (IQR 0.1–2.24) vs. 6.6 µg/ml (IQR 2.3–11.3), p < 0.001). ADA were undetectable in all the measured samples in maintenance. Conclusion This real-world experience confirms a drug exposure-endoscopic response relationship. Week 16 seems to be an appropriate time point to monitor drug exposure. Earlier USK TLs, at week 8, appear less valuable to be monitored due to the influence of initial IV dose. The absence of immunogenicity suggests that it is not a key driver in the loss of response.


2018 ◽  
Vol 36 (3) ◽  
pp. 194-201 ◽  
Author(s):  
Rafael Gil-Borras ◽  
Carlos García-Ballesteros ◽  
Carmen Benet-Campos ◽  
Ignacio Catalán-Serra ◽  
Francisca López-Chuliá ◽  
...  

Background/Aims: B1a cells (CD19+CD5+) are considered elements of the innate immune system. The aim of this study was to evaluate the frequency of B1a cells in the peripheral blood of patients with Crohn’s disease (CD) and its relation with disease severity. Methods: In this prospective study, a total of 128 subjects (64 CD patients and 64 healthy controls) were studied. B1a cells in peripheral blood, CD Activity Index, and Simple Endoscopic Score of B1a cells were studied. Results: A significant decrease of B1a cells in peripheral blood was observed in patients with CD versus controls (p = 0.002), especially in perforating or penetrating patterns (p = 0.017). A lower frequency of B1a cells is related to increased endoscopic severity (Spearman’s Rho: –0.559, p = 0.004). The mean frequency of B1a cells in patients with pre- and post-study surgery was significantly lower than that in patients who did not undergo surgery (p = 0.050 and p = 0.026, respectively). Conclusions: The B1a cell count in peripheral blood is lower in CD patients. This decrease is directly related to the severity of the disease (penetrating or perforating, Simple Endoscopy Score and surgery complication). These results pointed to the fact that B1a cells play an important role in immune protection in CD.


2020 ◽  
Author(s):  
Su-Mi Lee ◽  
Kyung-Hwa Lee ◽  
Seon-Young Park ◽  
Jin Ook Chung ◽  
Dong Hyun Kim ◽  
...  

Abstract Backgrounds: Cysteine-rich angiogenic inducer 61 (Cyr61) is emerging as an important regulator of tissue homeostasis and wound repair. We aim to explore the colonic mucosal expression of Cyr61 and analyze the association between Cyr61 expression and clinical course in patients with Crohn’s disease (CD).Methods: Endoscopic samples were identified from 83 CD patients with and 372 controls without any pathologic findings by searching pathological reports. Among them, age- and sex- matched 43 of each group by a propensity score were selected to compare Cyr61 expression by immunohistochemistry (IHC). IHC scores for Cyr61 expression of CD patients were divided into tertiles to evaluate the association with clinical course. Results: The mean IHC scores for Cyr61 expression was higher in CD patients (86.5) than in controls (46.1, P<0.001). In CD patients, the mean IHC scores for Cyr61 expression (68.3) was lower in patients with clinical recurrence than in patients without recurrence (92.2, P=0.01). When CD patients were stratified into tertile groups according to IHC scores for Cyr61 expression, clinical recurrence rates tended to be lower in patients with high Cyr61 expression (P for trend=0.02). Compared with tertile 1 of Cyr61 expression, tertile 3 of Cyr 61 expression was associated with reduced risk of clinical recurrence (OR 0.43, 95%CI 0.20~0.92) after adjustment for age, sex and CD activity index at the time of colonoscopy in CD patients (P=0.03). Conclusions: Cyr61 mucosal expression in CD patients was inversely associated with clinical course. In the future, the possible therapeutic role of Cyr61 should be considered.


2021 ◽  
Vol 15 (Supplement_1) ◽  
pp. S033-S034
Author(s):  
P Bossuyt ◽  
M Ferrante ◽  
F Baert ◽  
S Danese ◽  
B G Feagan ◽  
...  

Abstract Background Endoscopic healing has become a critical treatment target in Crohn’s disease (CD). Risankizumab (RZB), a humanized immunoglobulin G1 monoclonal antibody against the p19 subunit of interleukin 23, is being investigated as a treatment for moderate-to-severe CD. This analysis assessed different endoscopic endpoints in patients treated with RZB induction therapy in two double-blind, randomised, placebo (PBO)-controlled studies (ADVANCE [NCT03104413] and MOTIVATE [NCT03105128]). Methods Patients with moderate-to-severe CD (CD Activity Index [CDAI] of 220–450, Simple Endoscopic Score for CD [SES-CD] ≥ 6 [≥ 4 for isolated ileal disease] excluding the narrowing component, and average daily [liquid/very soft] stool frequency [SF] ≥ 4 and/or average daily abdominal pain [AP] score ≥ 2) who had demonstrated prior inadequate response or intolerance to conventional and/or biologic treatment (ADVANCE) or to biologic treatment (MOTIVATE) were randomised 2:2:1 (ADVANCE) or 1:1:1 (MOTIVATE) to receive intravenous (IV) RZB 600 mg, RZB 1200 mg, or PBO at weeks 0, 4, and 8. This analysis evaluated the proportion of patients who achieved endoscopic remission ulcer-free endoscopy (ie, absence of ulcers), and composite endpoints of CDAI clinical response and endoscopic response, and enhanced clinical response and endoscopic response at week 12 (endpoints defined in Figure 1 footnotes). All endoscopies were centrally read by a blinded reviewer. Safety was assessed throughout the studies. Results In ADVANCE and MOTIVATE, 850 and 569 patients, respectively, were randomised and included in the intent-to-treat population for this analysis. At week 12 greater proportions of RZB- vs PBO-treated patients in both studies achieved endoscopic remission (P ≤ .001), ulcer-free endoscopy (P ≤ .01), CDAI clinical response and endoscopic response (P ≤ .001), and enhanced clinical response and endoscopic response (P ≤ .001; Figure 1). Treatment with RZB 600 mg or 1200 mg was well tolerated, and no new safety risks were identified.1,2 Conclusion Induction therapy with IV RZB 600 mg or 1200 mg resulted in improved outcomes at week 12 compared with PBO as assessed by endoscopy and by composite endoscopic-clinical endpoints in patients with moderate-to-severe CD. References


2021 ◽  
Vol 15 (Supplement_1) ◽  
pp. S001-S002
Author(s):  
P M Irving ◽  
B E Sands ◽  
T Hoops ◽  
J L Izanec ◽  
L L Gao ◽  
...  

Abstract Background We studied the efficacy and safety of ustekinumab (UST) vs adalimumab (ADA) through 1 year in biologic-naïve patients (pts) with moderate-to-severe Crohn’s disease. Methods SEAVUE was a multicenter, randomized, blinded, parallel-group, active-controlled study in adults with CD Activity Index (CDAI) scores ≥220/≤450. Biologic-naïve pts failing/intolerant to conventional therapy with any size ulcer on baseline (BL) ileocolonoscopy were eligible. Pts were randomized 1:1 to UST (⁓6mg/kg IV at BL then 90mg SC every 8 weeks [Ws]) or ADA (160/80mg SC at BL/W2, then 40mg SC every 2 Ws) per US-approved regimens (no dose modifications). Primary endpoint was clinical remission at W52 (CDAI &lt;150). Major secondary endpoints were corticosteroid-free remission, clinical response (≥100-point CDAI decrease from BL), remission in pt-reported CDAI components (PRO-2 symptom remission: abdominal pain mean daily score ≤1 and stool frequency mean daily score ≤3), and endoscopic remission (SES-CD score ≤3/0 for pts with BL score=3) at W52 and clinical remission at W16. Results 386 pts were randomized to UST or ADA. BL demographics and disease characteristics were balanced between groups and indicative of pts with early, moderate-to-severe CD (median CD duration, 2.58 years; CDAI, 289.5; SES-CD, 8.0). At W52, 65% of UST-treated and 61% of ADA-treated pts achieved clinical remission (Δ=4.0%; 95% CI, -5.5%, 13.5%; p=0.417). Major secondary endpoints, including endoscopic remission, were similar between groups (Table 1), as were remission rates at assessment points through W52. Some other secondary endpoints showed numerical (not statistical) differences between UST and ADA (Table 1). Key safety events are summarized in Table 2. Among UST-treated and ADA-treated pts, 34.0% and 40.5% had infections, 2.6% and 7.2% had serious adverse events (AEs) of worsening CD, and 6.3% and 11.3% had AEs that led to discontinuation (DC) of study drug, respectively. One ADA-treated pt had active pulmonary TB. Injection-site reactions associated with active treatment occurred in 1.0% of UST-treated and 10.3% of ADA-treated pts. Overall, 15.2% of UST-treated and 23.6% of ADA-treated pts DC before W52. Reasons for DC were primarily lack of efficacy (UST, 2.1% vs ADA, 5.1%), AEs (UST, 5.7% vs ADA, 10.7%), and withdrawal of consent (UST, 5.8% vs ADA, 5.1%). Time to treatment DC was longer with UST vs ADA (post hoc analysis). Conclusion Both UST and ADA were highly effective in this population of biologic-naïve pts. Rates of clinical remission at W52 were not statistically significantly different between treatment groups. DC rates were numerically lower for UST. Safety results were consistent with prior experience for both treatments.


2018 ◽  
Vol 24 (10) ◽  
pp. 2266-2271 ◽  
Author(s):  
Konstantinos Papamichael ◽  
Shana Rakowsky ◽  
Claudio Rivera ◽  
Adam S Cheifetz ◽  
Mark T Osterman

Abstract Background and aim Objective and more rigorous therapeutic outcomes are emerging as novel targets in Crohn’s disease (CD). We investigated the association between maintenance serum infliximab trough concentrations and biochemical, endoscopic, or histologic remission in CD. Methods This retrospective multicenter study involved consecutive CD patients treated with infliximab who had a serum C-reactive protein (CRP) measured within 1 week or endoscopic evaluation within 12 weeks of therapeutic drug monitoring between January 2010 and June 2016. Biochemical remission was defined as a normal CRP (≤5 mg/L). Endoscopic remission was defined as absence of any mucosal break (ulceration or erosion) or for patients with an ileocolonic resection, a Rutgeerts score of ≤i1. Histologic remission was defined as absence of active inflammation. Results Seventy-one CRP levels and 96 colonoscopies from 110 CD patients were evaluated. Based on ROC analyses, infliximab concentration thresholds of 2.2, 9.7, and 9.8 μg/mL were found to be related with biochemical, endoscopic, and histologic remission, respectively. Multiple logistic regression analyses identified infliximab concentration ≥2.2 (OR 6.4; 95% CI, 1.5–27.1; P = 0.011), ≥9.7 (OR 3.6; 95% CI, 1.4–9; P = 0.006) and ≥9.8 μg/mL (OR 3.2; 95% CI, 1.3–7.9; P = 0.011) as variables independently associated with biochemical, endoscopic, and histologic remission, respectively. Conclusions This study showed that higher maintenance infliximab trough concentrations are associated with more favorable rates of biochemical, endoscopic, or histologic remission in CD patients and that infliximab concentrations may differ based on the treatment goal.


2020 ◽  
Vol 14 (Supplement_1) ◽  
pp. S052-S053 ◽  
Author(s):  
E Dreesen ◽  
S Berends ◽  
D Laharie ◽  
G D’Haens ◽  
S Vermeire ◽  
...  

Abstract Background Less than 50% of patients with Crohn’s disease (CD) starting infliximab (IFX) therapy achieve endoscopic remission (ER). Evidence for the benefits of pharmacokinetic (PK) and pharmacodynamic (PD) monitoring remains scarce. We aimed to develop a population (pop)PK/PD model to characterise the IFX dose-exposure-biomarker-response (faecal calprotectin [fCal] and ER) relationship in patients with CD. Methods Analyses were performed using data of a phase 4 dose-escalation study (TAILORIX). Patients started standard 5 mg/kg IFX induction therapy at weeks [w]0, 2 and 6. From w14 through w54, the IFX dose could be irreversibly doubled based on one of the three monitoring algorithms.1 Endoscopies were performed at w0, 12 and 54. Three sequential models were developed: A 2-compartment popPK model linking IFX dose to exposure, an indirect response popPK-PD model describing the inhibitory effect of IFX exposure on fCal, and a first-order Markov popPD model linking fCal to transitions between states of ER (CD endoscopic index of severity &lt;3), no ER and dropout (Figure 1). All modelling and simulation were performed using NONMEM 7.4. Results The study included 116/122 (95%) patients with CD enrolled in TAILORIX who had ≥1 detectable IFX serum concentration. In the developed models, it was shown that IFX clearance increased with increasing fCal, decreasing albumin, increasing CD activity index and presence of antibodies to IFX (transiently). Baseline fCal increased with increasing CRP and decreasing platelet count. Lower fCal increased probability of attaining ER and decreased probability of losing ER. Probability of dropping out given an earlier state of absence of ER increased with elapsing time. Simulations of 150 000 patients receiving 5, 7.5 or 10 mg/kg IFX (1:1:1) resulted in a flat dose–response curve due to large interindividual variability in PK and PD (Figure 2, top panels). The predicted fraction of patients achieving ER at w12 was 45.1% [30.3–60.5] (median [IQR]) when on 5 mg/kg IFX (~46.4% observed in data). However, simulations of 10 mg/kg IFX induction doses predicted only a slight increase in the fraction of patients achieving ER at w12 to 47.5% [32.0–62.6]. This minor benefit at the population level argues against systematic 10 mg/kg induction dosing in all patients. A similar observation was done during maintenance therapy, where 70.8% [62.6–75.5] of all simulated patients maintained ER at w54 (~72.2% observed in data) (Figure 2, right panels). Conclusion Model-informed infliximab dose optimisation towards a predefined fCal concentration—while accounting for PK and PD variability—may improve the effectiveness of infliximab therapy (eg. 64% chance of ER at w12 ~100 μg/g fCal at w6). Reference


2020 ◽  
Author(s):  
Su-Mi Lee ◽  
Kyung-Hwa Lee ◽  
Seon-Young Park ◽  
Jin Ook Chung ◽  
Dong Hyun Kim ◽  
...  

Abstract Backgrounds: Cysteine-rich angiogenic inducer 61 (Cyr61) is emerging as an important regulator of tissue homeostasis and wound repair. We aim to explore the colonic mucosal expression of Cyr61 and analyze the association between Cyr61 expression and clinical course in patients with Crohn’s disease (CD).Methods: Endoscopic samples were identified from 83 CD patients with and 372 controls without any pathologic findings by searching pathological reports. Among them, age- and sex- matched 43 of each group by a propensity score were selected to compare Cyr61 expression by immunohistochemistry (IHC). IHC scores for Cyr61 expression of CD patients were divided into tertiles to evaluate the association with clinical course. Results: The mean IHC scores for Cyr61 expression was higher in CD patients (86.5) than in controls (46.1, P<0.001). In CD patients, the mean IHC scores for Cyr61 expression (68.3) was lower in patients with clinical recurrence than in patients without recurrence (92.2, P=0.01). When CD patients were stratified into tertile groups according to IHC scores for Cyr61 expression, clinical recurrence rates tended to be lower in patients with high Cyr61 expression (P for trend=0.02). Compared with tertile 1 of Cyr61 expression, tertile 3 of Cyr 61 expression was associated with reduced risk of clinical recurrence (OR 0.43, 95%CI 0.20~0.92) after adjustment for age, sex and CD activity index at the time of colonoscopy in CD patients (P=0.03). Conclusions: Cyr61 mucosal expression in CD patients was inversely associated with clinical course. In the future, the possible therapeutic role of Cyr61 should be considered.


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