European registry on helicobacter pylori management: Effectiveness of first and second-line treatment in Spain

antibiotics Article European Registry on Helicobacter pylori Management: Effectiveness of First and Second-Line Treatment in Spain María Caldas 1,Ángeles Pérez-Aisa 2, Manuel Castro-Fernández 3, Luis Bujanda 4, Alfredo J. Lucendo 5, Luis Rodrigo 6, Jose M. Huguet 7, Jorge Pérez-Lasala 8, Javier Molina-Infante 9, Jesús Barrio 10, Luis Fernández-Salazar 11,Ángel Lanas 12, Mónica Perona 13, Manuel Domínguez-Cajal 14, Juan Ortuño 15, Blas JoséGómez-Rodríguez 16, Pedro Almela 17, Josep María Botargués18,Óscar Núñez 19, Inés Modolell 20, Judith Gómez 21, Rafael Ruiz-Zorrilla 22, Cristóbal De la Coba 23, Alain Huerta 24, Eduardo Iyo 25, Liliana Pozzati 26, Rosario Antón27, MercéBarenys 28, Teresa Angueira 5, Miguel Fernández-Bermejo 29, Ana Campillo 30, Javier Alcedo 31 , Ramón Pajares-Villaroya 32, Marianela Mego 33, Fernando Bermejo 34, JoséLuis Dominguez-Jiménez 35, Llúcia Titó36, Nuria Fernández 2, Manuel Pabón-Carrasco 37 ,Ángel Cosme 4, Pilar Mata-Romero 9, Noelia Alcaide 11, Inés Ariño 12, Tommaso Di Maira 15 , Ana Garre 1, Ignasi Puig 38 , Olga P. Nyssen 1, Francis Megraud 39 , Colm O’Morain 40, Javier P. Gisbert 1,* and on behalf of the Hp-EuReg Investigators   Citation: Caldas, M.; Pérez-Aisa, Á.; Castro-Fernández, M.; Bujanda, L.; Lucendo, A.J.; Rodrigo, L.; Huguet, J.M.; Pérez-Lasala, J.; Molina-Infante, J.; Barrio, J.; et al. European Registry on Helicobacter pylori Management: Effectiveness of First and Second-Line Treatment in Spain. Antibiotics 2021, 10, 13. https://dx.doi.org/ antibiotics10010013 Received: 1 December 2020 Accepted: 21 December 2020 Published: 25 December 2020 Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. Copyright: © 2020 by the authors. Licensee MDPI, Basel, Switzerland. This articleisan open accessarticledistributed under the terms and conditions of the Creative Commons Attribution(CC BY) license(https://creativecommons.org/ licenses/by/4.0/). 1Gastroenterology Unit, Hospital Universitario de La Princesa, Instituto de Investigación Sanitaria Princesa (IIS-IP), Universidad Autónoma de Madrid (UAM) and Centro de Investigación Biomédica en Red de Enfermedades Hepáticas y Digestivas (CIBERehd), 28006 Madrid, Spain; [email protected] (M.C.); anagarr[email protected] (A.G.); [email protected] (O.P.N.) 2 Digestive Unit, Agencia Sanitaria Costa del Sol, Red de Investigación en Servicios de Salud en Enfermedades Crónicas (REDISSEC), 29651 Marbella, Spain; [email protected] (Á.P.-A.); [email protected] (N.F.) 3Department of Gastroenterology, Hospital de Valme, 41014 Sevilla, Spain; [email protected] 4Department of Gastroenterology, Hospital Donostia/Instituto Biodonostia and CIBERehd, Universidad del País Vasco (UPV/EHU), 20014 San Sebastián, Spain; [email protected] (L.B.); [email protected] (Á.C.) 5Department of Gastroenterology, Hospital General de Tomelloso and CIBERehd, 13700 Ciudad Real, Spain; [email protected] (A.J.L.); [email protected] (T.A.) 6Gastroenterology Unit, Hospital Central de Asturias, 33011 Oviedo, Spain; [email protected] 7Gastroenterology Unit, Consorcio Hospital General Universitario de Valencia, 46014 Valencia, Spain; [email protected] 8Digestive Service, HM Sanchinarro, 28050 Madrid, Spain; jper[email protected] 9Department of Gastroenterology, Hospital San Pedro de Alcántara and CIBERehd, 10003 Cáceres, Spain; javier[email protected] (J.M.-I.); pilar[email protected] (P.M.-R.) 10 Department of Gastroenterology, Hospital Universitario Río Hortega, 47012 Valladolid, Spain; [email protected] 11 Digestive Service, Hospital Clínico Universitario de Valladolid, 47003 Valladolid, Spain; [email protected] (L.F.-S.); [email protected] (N.A.) 12 Digestive Service, Hospital Clínico Universitario Lozano Blesa and CIBERehd, 50009 Zaragoza, Spain; [email protected] (Á.L.); [email protected] (I.A.) 13 Gastroenterology Unit, Hospital Quirón Marbella, 29603 Málaga, Spain; [email protected] 14 Digestive Service, Hospital General San Jorge, 22004 Huesca, Spain; [email protected] 15 Digestive Service, Hospital Universitari y Politècnic La Fe de Valencia and CIBERehd, 46026 Valencia, Spain; [email protected] (J.O.); [email protected] (T.D.M.) 16 Digestive Service, Hospital Universitario Virgen Macarena, 41009 Sevilla, Spain; [email protected] 17 Digestive Service, Hospital Universitari General de Castelló, 12004 Castellón, Spain; [email protected] 18 Digestive Service, Hospital Universitari de Bellvitge, 08907 Barcelona, Spain; jbotar[email protected] 19 Digestive Service, Hospital Universitario Sanitas La Moraleja, 28050 Madrid, Spain; [email protected] 20 Digestive Service, Consorci Sanitari de Terrassa, 08191 Barcelona, Spain; [email protected] 21 Digestive Service, Complejo Asistencial Universitario de Burgos, 09006 Burgos, Spain; [email protected] 22 Digestive Service, Hospital Sierrallana, 39300 Cantabria, Spain; [email protected] 23 Digestive Service, Hospital de Cabueñes, 33394 Asturias, Spain; [email protected] 24 Digestive Service, Hospital de Galdakao-Usansolo, 48960 Vizcaya, Spain; ALAIN.HUERT[email protected] Antibiotics 2021,10, 13. https://dx.doi.org/10.3390/antibiotics10010013 https://www.mdpi.com/journal/antibiotics Antibiotics 2021,10, 13 2 of 15 25 Digestive Service, Hospital Comarcal de Inca, 07300 Mallorca, Spain; eduardoy[email protected] 26 Digestive Service, Hospital de Mérida, 06800 Badajoz, Spain; [email protected] 27 Digestive Medicine Department, Hospital Clínic Universitari de Vàlencia, 46010 Valencia, Spain; [email protected] 28 Digestive Service, Hospital de Viladecans, 08840 Barcelona, Spain; mbar[email protected] 29 Digestive Service, Clínica San Francisco, 10002 Cáceres, Spain; [email protected] 30 Digestive Service, Hospital Reina Sofía, Tudela, 31500 Navarra, Spain; [email protected] 31 Digestive Service, Hospital de Barbastro, 22300 Huesca, Spain; [email protected] 32 Digestive Service, Hospital Infanta Sofía, 28703 Madrid, Spain; [email protected]g 33 Digestive Service, Hospital Universitario General de Catalunya, 08195 Barcelona, Spain; [email protected] 34 Digestive Service, Hospital Universitario de Fuenlabrada, idiPAZ, 28942 Madrid, Spain; [email protected] 35 Digestive Service, Hospital Alto del Guadalquivir, 23740 Jaén, Spain; [email protected] 36 Digestive Service, Hospital de Mataró, 08304 Barcelona, Spain; [email protected] 37 Digestive Service, Centro Universitario de Cruz Roja, Universidad de Sevilla, 41004 Sevilla, Spain; [email protected] 38 Digestive Service, Althaia Xarxa Assistencial Universitària de Manresa and Universitat de Vic-Universitat Central de Catalunya (UVicUCC), 08242 Manresa, Spain; [email protected] 39 Laboratoire de Bactériologie, Hôpital Pellegrin, Bordeaux & INSERM U1053 BaRITOn, Universitéde Bordeaux, 33076 Bordeaux, France; [email protected] 40 Department of Clinical Medicine, Trinity College Dublin, D24 NR0A Dublin, Ireland; [email protected] *Correspondence: javier[email protected]; Tel.: +34-913093911; Fax: 34-915204013 Abstract: The management of Helicobacter pylori infection has to rely on previous local effectiveness due to the geographical variability of antibiotic resistance. The aim of this study was to evaluate the effectiveness of first and second-line H. pylori treatment in Spain, where the empirical prescription is recommended. A multicentre prospective non-interventional registry of the clinical practice of European gastroenterologists concerning H. pylori infection (Hp-EuReg) was developed, including patients from 2013 until June 2019. Effectiveness was evaluated descriptively and through a multivariate analysis concerning age, gender, presence of ulcer, proton-pump inhibitor (PPI) dose, therapy duration and compliance. Overall, 53 Spanish hospitals were included, and 10,267 patients received a first-line therapy. The best results were obtained with the 10-day bismuth single-capsule therapy (95% cure rate by intention-to-treat) and with both the 14-day bismuth-clarithromycin quadruple (PPI-bismuth-clarithromycin-amoxicillin, 91%) and the 14-day non-bismuth quadruple concomitant (PPI-clarithromycin-amoxicillin-metronidazole, 92%) therapies. Second-line therapies were prescribed to 2448 patients, with most-effective therapies being the triple quinolone (PPI-amoxicillin-levofloxacin/moxifloxacin) and the bismuth-levofloxacin quadruple schemes (PPI-bismuth-levofloxacin-amoxicillin) prescribed for 14 days (92%, 89% and 90% effectiveness, respectively), and the bismuth single-capsule (10 days, 88.5%). Compliance, longer duration and higher acid inhibition were associated with higher effectiveness. “Optimized” H. pylori therapies achieve over 90% success in Spain. Keywords: Helicobacter pylori; treatment; first-line; second-line; Spain 1. Introduction Helicobacter pylori (H. pylori) is a gram-negative bacterium with an estimated prevalence in southern Europe of 50%, involved in several important diseases such as chronic gastritis, peptic ulcer disease and gastric cancer, as well as in some important extra-gastric diseases such as iron deficiency anaemia or idiopathic thrombocytopenic purpura, among others [ 1 – 5 ]. These two factors are enough to explain the importance of finding a successful therapy able to eliminate the bacterium with the least amount of antibiotic treatment attempts. This is especially important considering the effect of antibiotics on the patient’s gut microbiota and the emergence of multi-resistant bacterial strains worldwide [6–8]. Antibiotics 2021,10, 13 3 of 15 However, an effective global treatment has not been found. Although several factors might be considered, the geographical variability of antibiotic resistance among different H. pylori strains (due to previous antibiotic exposure of both the patient and the community) represents an important obstacle, especially considering the extended recommendation of using empirical prescriptions [ 1 , 9 , 10 ]. In this sense, clarithromycin, metronidazole and levofloxacin, antibiotics frequently used against H. pylori, have shown at least moderate resistance rates in southern Europe and specifically in Spain, which has justified the emergence of numerous and varied optimization strategies [9,11,12]. With the aim of obtaining updated information on H. pylori treatment in Spain and to find strategies to improve therapies in this area, we designed this long-term prospective clinical practice study. 2. Results 2.1. Baseline Characteristics In total, 53 Spanish hospitals were selected (Supplementary Materials Figure S1) and 14,128 patients were included for the descriptive demographic analysis (Table 1). Table 1. Baseline characteristics of firstand second-line treatments. Variables Overall N (%) 1st Line N (%) 2nd Line N (%) 14,128 10,633 2481 Gender Female 8795 (62) 6477 (61) 1632 (66) Male 5320 (38) 4146 (39) 847 (34) Age, mean (standard deviation) 50 ±15 51 ±14.7 50 ±14.5 Penicillin allergy Presence 644 (4.6) 435 (4.1) 151 (6.1) Indication Dyspepsia 9152 (65) 6823 (64) 1656 (67) Ulcer disease 2103 (15) 1554 (15) 393 (16) Others 2868 (20) 2251 (21) 432 (17) Diagnostic tests Required endoscopy 8180 (58) 6672 (63) 1061 (43) Culture Performed NA 366 (3.4) NA No resistance 199 (54) Clarithromycin R 52 (14) Metronidazole R 93 (25) Clarithromycin and metronidazole R 18 (4.9) Levofloxacin R 63 (17) Treatment length 7 days 182 (1.3) 160 (1.5) 17 (0.7) 10 days 8615 (61) 6670 (63) 1382 (56) 14 days 5273 (37) 3764 (35) 1074 (43) Others 58 (0.4) 39 (0.4) 8 (0.3) Proton pump inhibitor dose Low 5110 (37) 4063 (39) 751 (31) Standard 3290 (24) 2605 (25) 458 (19) High 5496 (39) 3834 (36) 1239 (50) Compliance No (<90% drug intake) 415 (2.9) 304 (3) 69 (2.8) Yes ( ≥ 90% drug intake) 13,159 (93) 9932 (93) 2302 (92.8) Unknown 554 (3.9) 397 (4) 110 (4.4) N, total of patients included; %, proportion of patients included; R, resistance; NA, not applicable; Low, ≈ 20 mg omeprazole equivalents b.i.d.; Standard, ≈40 mg omeprazole equivalents b.i.d.; High, ≈60 mg omeprazole equivalents b.i.d. 2.2. Treatment Use and Effectiveness 2.2.1. First-Line Treatment A total of 10,267 patients received an empirical first-line treatment. The most frequently prescribed regimens were: non-bismuth quadruple concomitant therapy (PPIclarithromycin-amoxicillin-metronidazole, all four drugs administered concomitantly, Antibiotics 2021,10, 13 4 of 15 n= 4051, 40%), standard triple regimen (PPI-clarithromycin-amoxicillin, n= 2712, 26%), bismuth quadruple therapy (bismuth single-capsule, marketed as Pylera ® (Allergan, Inc Dublin, IE) containing tetracycline-metronidazole-bismuth salts administered together with a PPI, n= 1660, 16%), bismuth-clarithromycin quadruple therapy (PPI-clarithromycinamoxicillin-bismuth, n= 1055, 10%), non-bismuth sequential quadruple regimen (PPIamoxicillin during five days, followed by PPI-clarithromycin-metronidazole during the five remaining days, n= 230, 2.2%) and clarithromycin-metronidazole triple therapy (PPIclarithromycin-metronidazole, n= 124, 1.2%). The prescription trends over time, as shown in Figure 1. Antibiotics 2021, 10, x FOR PEER REVIEW 4 of 16 with a PPI, n = 1660, 16%), bismuth-clarithromycin quadruple therapy (PPI-clarithromycin-amoxicillin-bismuth, n = 1055, 10%), non-bismuth sequential quadruple regimen (PPIamoxicillin during five days, followed by PPI-clarithromycin-metronidazole during the five remaining days, n = 230, 2.2%) and clarithromycin-metronidazole triple therapy (PPIclarithromycin-metronidazole, n = 124, 1.2%). The prescription trends over time, as shown in Figure 1. Figure 1. Prescription trends in first- (A) Type of therapy; (B) Duration of therapy; (C) Dose of PPI and second-line (D) Type of therapy; (E) Duration of therapy; (F) Dose of PPI treatment. PPI: proton-pump inhibitor, C: clarithromycin, A: amoxicillin, M: metronidazole, Single-capsule: three-in-one single capsule, Bi: bismuth, Conc: concomitant administration, Seq: sequential administration, L: levofloxacin, Mx: Moxifloxacin, Low: ≈20 mg omeprazole equivalents b.i.d., Standard: ≈40 mg omeprazole equivalents b.i.d., High: ≈60 mg omeprazole equivalents b.i.d. Overall effectiveness of the first-line therapies reached 88% on the mITT analysis. The highest effectiveness was obtained with the bismuth single-capsule (95%), the bismuthclarithromycin therapy (91%) and the concomitant therapy (90%) (Table 2). Adverse events (AE) appeared in 25% of the patients; however, most of them were of mild intensity (62%) and only 0.2% of the patients presented a serious AE. Compliance was higher than 97% (see Table S1 and File S2 for a detailed analysis of safety). Figure 1. Prescription trends in first- ( A ) Type of therapy; ( B ) Duration of therapy; ( C ) Dose of PPI and second-line ( D ) Type of therapy; ( E ) Duration of therapy; ( F ) Dose of PPI treatment. PPI: proton-pump inhibitor, C: clarithromycin, A: amoxicillin, M: metronidazole, Single-capsule: three-in-one single capsule, Bi: bismuth, Conc: concomitant administration, Seq: sequential administration, L: levofloxacin, Mx: Moxifloxacin, Low: ≈ 20 mg omeprazole equivalents b.i.d., Standard: ≈40 mg omeprazole equivalents b.i.d., High: ≈60 mg omeprazole equivalents b.i.d. Overall effectiveness of the first-line therapies reached 88% on the mITT analysis. The highest effectiveness was obtained with the bismuth single-capsule (95%), the bismuthclarithromycin therapy (91%) and the concomitant therapy (90%) (Table 2). Adverse events (AE) appeared in 25% of the patients; however, most of them were of mild intensity (62%) and only 0.2% of the patients presented a serious AE. Compliance was higher than 97% (see Table S1 and File S1 for a detailed analysis of safety). The overall multivariate analysis performed with the first-line treatment showed that higher effectiveness was associated with good compliance (OR = 4.1; 95% CI: 3.0–5.5), extended therapies (10 days (OR = 4.5; 95% CI: 3.2–6.2) or 14 days length (OR = 4.1; 95% CI: 2.9–5.9)), higher gastric acid inhibition (standard (OR = 1.4; 95% CI: 1.2–1.7) or high PPI doses (OR = 2.1; 95% CI: 1.7–2.4)), presence of peptic ulcer (OR = 1.2; 95% CI: 1.0–1.5) and male gender (OR = 1.2; 95% CI: 1.1–1.4) (see Table 3for the analysis of each therapy). Antibiotics 2021,10, 13 5 of 15 Table 2. Effectiveness, safety and compliance of the most frequent therapies prescribed in the firstand second-line treatments. Effectiveness Adverse Events Compliance Treatment ITT mITT PP N (%) 95% CI N (%) 95% CI N (%) 95% CI N (%) 95% CI N (%) 95% CI 1st line 10,101 (83.5) 83–84 9726 (88) 88–89 9497 (89) 88–89 9937 (25) 25–26 9886 (97) 96–97 PPI + C + A + M (Conc) 3996 (86) 85–87 3880 (90) 89–91 3781 (90) 89–91 3963 (28) 26–29 3942 (97) 96–97 PPI + C + A 2712 (78) 76–80 2544 (83) 82–85 2498 (84) 82–85 2617 (15) 13–16 2598 (98) 97–98 PPI + Single–capsule 1574 (88) 86–89 1540 (95) 94–96 1514 (96) 95–97 1566 (25) 23–27 1562 (97) 96–98 PPI + Bi + C + A 1034 (88) 86–90 1015 (91) 89–93 1002 (91) 89–93 1019 (40) 37–44 1021 (98) 98–99 PPI + C + A + M (Seq) 230 (79) 73–84 222 (81.5) 76–86 192 (84) 79–89 230 (49) 42–55 222 (86.5) 81–91 PPI + C + M 124 (59) 50–68 113 (65) 55–73 112 (65) 65–74 119 (16) 10–24 118 (97.5) 93–99 2nd line 2420 (79) 77–80 2295 (84) 82–85 2247 (84) 82–86 2348 (28) 27–30 2342 (97) 96–98 PPI + L + A 944 (74) 71–77 893 (78.5) 76–81 881 (79) 76–82 919 (26) 23–29 908 (99) 98–99 PPI + Bi + L + A 463 (86) 83–89 451 (89) 86–92 435 (90) 87–93 454 (33) 28–37 459 (95) 93–97 PPI + Single–capsule 443 (80) 76–84 409 (88) 85–91 398 (89) 85–92 422 (31) 27–36 420 (96) 94–98 PPI + Mx + A 135 (87) 80–92 129 (91) 84–95 129 (91) 84–95 134 (19) 13–27 133 (99) 96–100 PPI + C + A + M (Conc) 120 (74) 65–82 110 (82) 73–89 109 (82) 73–88 112 (24) 17–33 112 (98) 94–100 ITT, intention-to-treat; mITT, modified intention-to-treat; PP, per protocol; N, total of patients included; %, proportion of patients presenting effectiveness/adverse events/compliance; CI, confidence interval; PPI, proton pump inhibitor; C, clarithromycin; A, amoxicillin; M, metronidazole; Single-capsule, three-in-one single capsule; Bi, bismuth; L: levofloxacin; Mx, moxifloxacin; Conc, concomitant administration; Seq, sequential administration. Antibiotics 2021,10, 13 6 of 15 Table 3. Multivariate analysis of patients treated with a first-line therapy. Variables Overall PPI+C+A+M (Conc) PPI + C + A PPI + Single-Capsule PPI + Bi + C + A PPI + C + A + M (Seq) OR (95% CI) p-Values OR (95% CI) p-Values OR (95% CI) p-Values OR (95% CI) p-Values OR (95% CI) p-Values OR (95% CI) p-Values Gender [R: Female] 1 1 1 1 1 1 Male 1.22 (1.07–1.40) 0.004 1.39 (1.11–1.75) 0.004 1.26 (1.00–1.59) 0.050 0.83 (0.51–1.34) 0.442 1.10 (0.79–1.74) 0.690 1.85 (0.84–4.04) 0.125 Age (years) [R: 18–30] 1 1 1 1 1 1 31–50 1.15 (0.92–1.44) 0.232 1.32 (0.92–1.90) 0.136 1.13 (0.77–1.65) 0.530 0.73 (0.24–2.18) 0.568 0.86 (0.38–1.95) 0.723 0.33 (0.07–1.57) 0.163 51–70 1.08 (0.86–1.35) 0.514 1.23 (0.86–1.77) 0.265 1.10 (0.75–1.61) 0.615 0.72 (0.24–2.12) 0.547 0.82 (0.37–1.85) 0.634 0.32 (0.07–1.62) 0.170 ≥71 1.18 (0.87–1.59) 0.289 1.29 (0.78–2.12) 0.327 1.26 (0.76–2.08) 0.369 0.70 (0.20–2.47) 0.575 0.65 (0.24–1.79) 0.406 0.23 (0.03–1.53) 0.128 Presence of ulcer [R: No] 1 1 1 1 1 1 Yes 1.23 (1.01–1.49) 0.042 1.15 (0.83–1.60) 0.389 1.48 (1.07–2.04) 0.019 1.02 (0.50–2.10) 0.950 3.12 (0.96–10.2) 0.059 0.93 (0.36–2.41) 0.875 Length (days) [R: 7] 1 NA 1 NA † NA NA ‡ 10 4.46 (3.20–6.23) 0.000 1 2.78 (1.92–4.04) 0.000 1 14 4.11 (2.88–5.87) 0.000 1.28 (0.98–1.66) 0.068 2.46 (1.60–3.77) 0.000 0.71 (0.06–8.54) 0.790 PPI dose of OE [R: Low] 1 1 1 1 1 1 Standard 1.42 (1.21–1.66) 0.000 0.98 (0.75–1.29) 0.888 2.14 (1.67–2.74) 0.000 1.50 (0.84–2.69) 0.168 6.69 (1.35–33.3) 0.020 1.99 (0.24–16.4) 0.521 High 2.05 (1.72–2.44) 0.000 1.59 (1.24–2.03) 0.000 3.54 (2.49–5.03) 0.000 1.97 (1.08–3.59) 0.027 2.26 (0.63–8.08) 0.211 0.56 (0.22–1.49) 0.244 Compliance [R: <90% DI] 1 1 1 1 1 1 ≥90% DI 4.07 (3.04–5.45) 0.000 3.41 (2.14–5.43) 0.000 7.12 (3.69–13.7) 0.000 16 (6.99–36.6) 0.000 1.78 (0.37–8.45) 0.469 2.98 (1.28–6.94) 0.011 Overall, the population receiving a first-line therapy; PPI, proton pump inhibitor; C, clarithromycin; A, amoxicillin; M, metronidazole; Single-capsule, three-in-one single capsule; Bi, bismuth; Conc, concomitant administration; Seq, sequential administration; OR, odds ratio; CI, confidence interval; R, category of reference used for the logistic regression; OE, omeprazole equivalent; DI, drug intake; NA, not applicable; † 99.7% of the patients received 10-days of therapy so comparison in length terms was not possible; ‡ 99.6% of the patients received 10-days of treatment so comparison in terms of length was not possible. Antibiotics 2021,10, 13 7 of 15 2.2.2. Second-Line Treatment A total of 2448 patients received an empirical second-line therapy. Five therapies were most frequently used: the levofloxacin-amoxicillin triple therapy (PPI-amoxicillinlevofloxacin, n= 944, 39%), the bismuth-levofloxacin quadruple therapy (PPI-amoxicillinlevofloxacin-bismuth, n= 475, 19.4%), the bismuth single-capsule (n= 454, 18.6%), the moxifloxacin-amoxicillin therapy (PPI-amoxicillin-moxifloxacin, n= 136, 5.6%) and the concomitant therapy (n= 121, 4.9%). Treatment prescriptions over time are depicted in Figure 1. Overall effectiveness of second-line therapies reached 84% on the mITT analysis. Highest effectiveness was obtained with the bismuth-levofloxacin therapy (89%) and the bismuth single-capsule (88%) (Table 2). AE were reported in 28% of the cases (49% and 47% of them being of moderate and mild intensity, respectively, and only one patient showing a serious AE). Compliance was higher than 95% (see Table S1 and File S1 for a detailed analysis of safety). The overall multivariate analysis performed with second-line treatment showed that higher effectiveness was associated with good compliance (OR = 3.4; 95% CI: 1.7–6.9), high PPI dose (OR = 1.9; 95% CI: 1.4–2.6) and 14-day therapy (OR = 1.5; 95% CI: 1.1–2.1) (See Table 4for the analysis of separated therapies considering only the three therapies more frequently used in second-line in Spain). Effectiveness by treatment duration and PPI doses in firstand secondline regimens are shown in Tables S2 and S3. Antibiotics 2021,10, 13 8 of 15 Table 4. Multivariate analysis of patients treated with a second-line therapy. Variables Overall PPI + L + A PPI + Bi + L + A PPI + Single-Capsule OR (95% CI) p-Values OR (95% CI) p-Values OR (95% CI) p-Values OR (95% CI) p-Values Gender [R: Female] 1 1 1 1 Male 1.39 (1.07–1.81) 0.014 1.03 (0.70–1.50) 0.898 2.83 (1.33–6.05) 0.007 0.96 (0.47–1.93) 0.898 Age [R: 18–30] 1 1 1 1 31–50 0.60 (0.36–0.99) 0.045 0.81 (0.39–1.70) 0.582 0.64 (0.17–2.34) 0.506 0.33 (0.07–1.52) 0.156 51–70 0.44 (0.27–0.73) 0.001 0.47 (0.23–0.97) 0.041 0.36 (0.10–1.29) 0.118 0.38 (0.08–1.73) 0.211 ≥71 0.37 (0.20–0.69) 0.002 0.43 (0.18–1.03) 0.059 0.24 (0.05–1.09) 0.064 0.73 (0.09–5.82) 0.766 Presence of ulcer [R: No] 1 1 1 1 Yes 1.07 (0.74–1.54) 0.729 1.04 (0.63–1.73) 0.869 1.97 (0.44–8.76) 0.374 0.79 (0.32–1.94) 0.600 Previous C [R: No] 1 1 1 NA † Yes 0.63 (0.33–1.21) 0.167 0.82 (0.16–4.12) 0.809 0.21 (0.03–1.79) 0.155 Length [R: 10] 1 1 1 14 1.51 (1.11–2.05) 0.009 3.88 (2.24–6.71) 0.000 3.12 (0.35–27.6) 0.307 0.64 (0.07–5.93) 0.692 PPI dose of OE [R: Low] 1 1 1 1 Standard 1.21 (0.88–1.65) 0.241 1.20 (0.81–1.79) 0.360 2.50 (0.40–15.5) 0.325 1.45 (0.56–3.77) 0.443 High 1.88 (1.37–2.59) 0.000 1.66 (0.99–2.77) 0.055 3.24 (1.09–9.59) 0.034 1.43 (0.72–2.87) 0.310 Compliance [R: <90% DI] 1 1 1 1 ≥90% DI 3.43 (1.71–6.88) 0.001 5.47 (1.27–23.5) 0.023 3.01 (0.91–9.99) 0.071 4.46 (1.02–19.5) 0.047 Overall, the population receiving a second-line therapy; PPI, proton pump inhibitor. L, levofloxacin; A, amoxicillin; Bi, bismuth; Single-capsule, three-in-one single capsule; OR, odds ratio; CI, confidence interval; R, category of reference used for the logistic regression; C, clarithromycin; OE, omeprazole equivalent; DI, drug intake; NA, not applicable; † 96% of the patients had previously received clarithromycin so comparison between both groups was not possible. Antibiotics 2021,10, 13 9 of 15 2.3. Penicillin Allergic Patients A total of 411 patients allergic to penicillin received an empirical first-line therapy, being the most frequent, the bismuth single-capsule (n= 154, 37.5%) and the clarithromycinmetronidazole therapy (n= 117, 28.5%). The overall effectiveness was 81% in first-line, although the bismuth single-capsule reached 94% mITT effectiveness. A second-line attempt was empirically used in 137 patients allergic to penicillin, being the bismuth single-capsule (n= 34, 24.8%), the most frequently used. Results on effectiveness, safety and compliance as well as effectiveness stratified by length and PPI dose, are shown in Tables S4–S6. 3. Discussion Treatment of H. pylori infection in Spain in firstand secondline, in which the empirical approach is generally recommended, still remains a challenge, especially considering the more demanding threshold of effectiveness required lately (90%) [ 6 ]. This has led to the progressive complexity of the regimens prescribed, which involve an increasing use of quadruple regimens, longer prescriptions (10–14 days) and higher PPI doses over time [1,9]. Concerning first-line treatment, we found an overall effectiveness of 88% in our cohort, close to the optimal threshold required, combined with an optimal safety profile [6,13]. Analysis of each specific therapy revealed that the standard triple therapy containing clarithromycin and amoxicillin, recommended throughout several years in Spain, only reached approximately 80% success, in line with previous evidence [ 14 ]. Its low effectiveness, together with the increasing clarithromycin resistance rates over time (up to 20% recently notified) led to the discontinuation of its use in our area [ 6 , 9 , 12 ]. This drop in prescriptions over time in our cohort brought with it the increase of use of quadruple therapies, such as the concomitant, the bismuth single-capsule and the bismuth-clarithromycin therapies, which also were, precisely, the therapies showing the highest effectiveness (≥90%). Concomitant treatment was the therapy most frequently used in first-line, in agreement with recommendations provided by national guidelines [ 9 ]. This therapy showed 90% effectiveness, similar to previous reports, and was mostly due to the relatively low dual resistance rates to both clarithromycin and metronidazole documented in our country [ 9 , 12 , 15 – 17 ]. With regard to the bismuth-clarithromycin quadruple therapy, a progressive rise on its prescription was seen over time, and it showed a very high effectiveness (91%), similar to previous evidence [ 18 ]. In fact, data coming from areas with higher clarithromycin resistance than Spain such as China still show high success of this therapy, which is thought to be at least partially compensated by the use of bismuth [ 19 ]. This is encouraging, assuming a hypothetical increase of clarithromycin resistance in Spain in the following years. The use of a bismuth quadruple therapy that contains tetracycline and metronidazole also avoids the problem of clarithromycin resistance due to the absence of this antibiotic and the low probability of developing resistance to components such as bismuth or tetracycline by H. pylori [ 9 , 20 ]. Moreover, the commercialization of a pill containing the three aforementioned drugs facilitated the access to tetracycline, which used to be hardly available in this area [ 9 , 21 ]. This therapy showed an eradication rate of 95% in our cohort, similar to what was described in a recently published meta-analysis [22]. When we analysed the variables associated with the increase of effectiveness, good compliance ( ≥ 90% of drug intake) showed the highest association for overall treatment and also for nearly all the therapies analysed individually. Other authors had previously reported this association [ 17 , 18 , 23 , 24 ]. Therefore, strategies designed to pursue the best compliance possible are needed. The use of standard PPI doses ( ≈ 40 mg omeprazole equivalents b.i.d.) or high PPI doses ( ≈ 60 mg omeprazole equivalents b.i.d.) showed higher effectiveness in our cohort in the overall analysis and in the concomitant, bismuth-clarithromycin and bismuth singlecapsule therapies. Previous reports had already shown a beneficial effect of higher grades