Efficacy and safety of ligelizumab in adults and adolescents with chronic spontaneous urticaria: results of two phase 3 randomised controlled trials

BACKGROUND

Many patients with chronic spontaneous urticaria (CSU) do not achieve complete control of their symptoms with current available treatments. In a dose-finding phase 2b study, ligelizumab improved urticaria symptoms in patients with H1-antihistamine (H1-AH) refractory CSU. Here, we report the efficacy and safety outcomes from two ligelizumab phase 3 studies.

METHODS

PEARL-1 and PEARL-2 were identically designed randomised, double-blind, active-controlled and placebo-controlled parallel-group studies. Patients aged 12 years or older with moderate-to-severe H1-AH refractory CSU were recruited from 347 sites in 46 countries and randomly allocated in a 3:3:3:1 ratio via Interactive Response Technology to 72 mg ligelizumab, 120 mg ligelizumab, 300 mg omalizumab, or placebo, dosed every 4 weeks, for 52 weeks. Patients allocated to placebo received 120 mg ligelizumab from week 24. The primary endpoint was change-from-baseline (CFB) in weekly Urticaria Activity Score (UAS7) at week 12, and was analysed in all eligible adult patients according to the treatment assigned at random allocation. Safety was assessed throughout the study in all patients who received at least one dose of the study drug. The studies were registered with ClinicalTrials.gov, NCT03580369 (PEARL-1) and NCT03580356 (PEARL-2). Both trials are now complete.

FINDINGS

Between Oct 17, 2018, and Oct 26, 2021, 2057 adult patients were randomly allocated across both studies (72 mg ligelizumab n=614; 120 mg ligelizumab n=616; 300 mg omalizumab n=618, and placebo n=209). A total of 1480 (72%) of 2057 were female, and 577 (28%) of 2057 were male. Mean UAS7 at baseline across study groups ranged from 29·37 to 31·10. At week 12, estimated treatment differences in mean CFB-UAS7 were as follows: for 72 mg ligelizumab versus placebo, -8·0 (95% CI -10·6 to -5·4; PEARL-1), -10·0 (-12·6 to -7·4; PEARL-2); 72 mg ligelizumab versus omalizumab 0·7 (-1·2 to 2·5; PEARL-1), 0·4 (-1·4 to 2·2; PEARL-2); 120 mg ligelizumab versus placebo -8·0 (-10·5 to -5·4; PEARL-1), -11·1 (-13·7 to -8·5; PEARL-2); 120 mg ligelizumab versus omalizumab 0·7 (-1·1 to 2·5; PEARL-1), -0·7 (-2·5 to 1·1; PEARL-2). Both doses of ligelizumab were superior to placebo (p<0·0001), but not to omalizumab, in both studies. No new safety signals were identified for ligelizumab or omalizumab.

INTERPRETATION

In the phase 3 PEARL studies, ligelizumab demonstrated superior efficacy versus placebo but not versus omalizumab. The safety profile of ligelizumab was consistent with previous studies.

FUNDING

Novartis Pharma.

Can bacterial lysates be useful in prevention of viral respiratory infections in childhood? The results of experimental OM-85 studies

Respiratory tract infections (RTI) are mainly viral in origin and among the leading cause of childhood morbidity globally. Associated wheezing illness and asthma are still a clear unmet medical need. Despite the continuous progress in understanding the processes involved in their pathogenesis, preventive measures and treatments failed to demonstrate any significant disease-modifying effect. However, in the last decades it was understood that early-life exposure to microbes, may reduce the risk of infectious and allergic disorders, increasing the immune response efficacy. These results suggested that treatment with bacterial lysates (BLs) acting on gut microbiota, could promote a heterologous immunomodulation useful in the prevention of recurrent RTIs and of wheezing inception and persistence. This hypothesis has been supported by clinical and experimental studies showing the reduction of RTI frequency and severity in childhood after oral BL prophylaxis and elucidating the involved mechanisms. OM-85 is the product whose anti-viral effects have been most extensively studied in vitro, animal, and human cell studies and in translational animal infection/disease models. The results of the latter studies, describing the potential immune training-based activities of such BL, leading to the protection against respiratory viruses, will be reported. In response to human rhinovirus, influenza virus, respiratory syncytial virus and severe acute respiratory coronavirus-2, OM-85 was effective in modulating the structure and the functions of a large numbers of airways epithelial and immune cells, when administered both orally and intranasally.

[Argentine guidelines for urticaria and angioedema]

This interdisciplinary paper summarizes the news in the diagnosis and treatment of chronic urticaria (CU), and provides concepts, definitions and evidence-based suggestions for its management. Urticaria occurs in at least 20% of the population at some point in their lives. Acute urticaria (less than 6 weeks' duration), differs from CU in its etiology, but the onset of this disease is always acute. CU may occur as spontaneous (SCU) or induced (ICU). The diagnosis is simple, although a careful evaluation is necessary for differential diagnosis. ICU's diagnosis is mainly clinical, even if provocation tests can be useful. Supplementary studies should be limited and based on the clinical suspicion. Treatment may be divided into three approaches: avoidance, elimination or treatment of the cause, and pharmacological treatment. Recently treatment has been modified with the use of second-generation antihistamines as first-line and increased doses of nonsedating H1 antihistamines, up to 4 times, as second line. Antihistamines are essential to treat CU; however, 40% of patients do not achieve good control despite increased doses and require additional treatment. The most recent evidence indicates a group of drugs to be used as third line in these cases, to improve quality of life and to limit toxicity from frequent or chronic use of systemic steroids. Only 3 drugs are recommended as third line: omalizumab, cyclosporin A or anti-leukotrienes.

Anaphylaxis in Latin American children and adolescents: the Online Latin American Survey on Anaphylaxis (OLASA)

OBJECTIVES

To identify the main clinical manifestations, triggers, and treatment of severe allergic reactions (SAR) in children and adolescents (n=191, up to 18 years of age) seen by allergologists and registered in the Online Latin American Survey of Anaphylaxis (OLASA).

RESULTS

53.0% of the patients were males and the aetiological agent was identified in 85.5% of them as follows: foods (36.1%), drugs (27.7%), and insect stings (26.2%). The most common symptoms during an acute episode were cutaneous (94.2%), and respiratory (78.5%). Most patients were treated in emergency setting, yet only 34.6% received parenteral epinephrine and 14.3% had to be hospitalised.

CONCLUSION

Cutaneous symptoms ranked the order of clinical presentation of SAR. Food was the main triggering agent in the younger cases and insect sting and drugs in the adolescents. Treatment provided for SAR was not appropriate. It is necessary to improve educational programmes in order to enhance the knowledge on this potentially fatal emergency.

Allergenicity of varieties of soybean

BACKGROUND

Soybean hulls (SHs) cause respiratory allergies. This study investigates the allergenicity of soybean varieties (SVs) by in vivo and in vitro tests.

METHODS

Ten SVs were studied: (a) five with a proved clinical relevance (SVs 1, 2, 3, 4, 5), the last four with a 'dull' phenotype; (b) five of undetermined relevance, three of them (SVs 6, 7, 8) with a 'shiny' phenotype, and two (SVs 9 and 10) with a 'dull' phenotype. Extracts from all 10 SVs were used to skin prick test (SPT) 21 subjects sensitized to SHs. Positive and negative sera pools prepared from sera of subjects sensitized or not to SHs, respectively, were utilized to perform in vitro experiments (specific IgE and IgG4 determinations, SDS-PAGE/IgE-Western blot, and IgE-inhibition).

RESULTS

In this study, it was found that 52.4, 52.4, 57.1, 71.4, 80.9, 42.9, 57.1, 71.4, 52.4, and 38.1% subjects had a positive SPT with SVs 1-10, respectively (P NS). Specific IgE values to SVs 1-10 obtained with the positive pool are 28.3, 26.4, 29.9, 28.3, 26.8, 4.8, 13.4, 6.7, 24.7, and 17.5% total counts bound, respectively; and specific IgG4 values 0.851, 0.818, 0.721, 1.609, 0.789, 0.617, 0.662, 0.0, 1.127, and 0.934 OD units, respectively; the microgram of protein required to produce 50% inhibition are 2.5, 3.7, 4.5, 2.4, 5, 39.8, 25.2, 25.1, 4.5, and 8.9, respectively. A 7-kDa band is present in all SVs except in those with a 'shiny' phenotype.

CONCLUSIONS

The SVs with a 'shiny' phenotype contain less allergens than the other SVs studied, as determined by in vitro tests. However, SPT results with the SVs do not differ. Genetic screens should be devised to select plants with reduced, preferably absent, allergenicity, but with a high nutritional value, and this allergenicity should be studied utilizing in vivo and in vitro tests.

Identification of the soybean hull allergens involved in sensitization to soybean dust in a rural population from Argentina and N-terminal sequence of a major 50 KD allergen

BACKGROUND

Sensitization to soybean hull (SH) allergens occurs in subjects from Argentina, a soybean producer country. However, the causative allergens have not been identified. The purposes of this study are to: (i) identify the SH allergens using sera of 29 subjects with asthma and/or allergic rhinitis from Argentina exposed to soybean dust who have a positive (weal with SH/weal with histamine > or = 0.5) skin prick test to SH; and (ii) determine the N-terminal amino acid sequence of a major 50 K SH allergen that sensitizes this population.

METHODS

All sera were assayed for specific IgE (RIA), IgG4 (ELISA), and IgE and IgG4-Western blots. A sera pool from 10 healthy subjects was a negative control. N-terminal amino acid sequencing was performed by the Edman degradation method.

RESULTS

Positive specific IgE only was found in 12/29 (41.4%), IgG4 in 3/29 (10.3%), and both IgE and IgG4 in 14/29 (48.3%) sera. IgE-Western blot demonstrates: (i) an allergen, MW 50 K (51.7% binding); (ii) one or two distinct allergens, MW < 20.2 K (72.4% binding), depending on the sera; and (iii) 1-5 additional IgE binding proteins, MW > 20.2 to < 46.9 K (41.4% binding), depending on the sera. IgG4-Western blot demonstrates: (i) a band, MW 70K (31% binding); (ii) a band, MW 50 K (17.2% binding); (iii) one or two additional bands, MW < 20.2 K (51.7% binding), depending on the sera; and (iv) a band, MW > 20.2 to < 28.5 K (20.7% binding). The 50 K allergen N-terminal amino acid sequence of the first 17 amino acids indicates a significant homology with chlorophyll A-B binding protein precursors from tomato, spinach, and petunia.

CONCLUSIONS

Specific IgE and IgG4 to SH are common in sera from allergic individuals living in rural areas in Argentina. SH contain an IgE binding protein, MW about 50 K, not previously described. Sensitization to this allergen is common in subjects who are repeatedly exposed to soybean dust inhalation.

Sensitization to soybean hull allergens in subjects exposed to different levels of soybean dust inhalation in Argentina

BACKGROUND

Soybean hulls (SHs) have been identified as the source of aeroallergens responsible for soybean asthma outbreaks. However, the prevalence of sensitization to SH allergens in subjects from Argentina, a country where soybeans are produced, is unknown.

OBJECTIVE

The purpose of this study was to determine the prevalence of sensitization to SH by in vivo and in vitro tests in subjects with asthma or allergic rhinitis and in control subjects from Argentina who have been exposed to different levels of soybean dust inhalation (SDI).

METHODS

Exposure to SDI is defined as follows: (1) direct = occupational, (2) indirect = proximity to soybean fields or grain elevators, and (3) urban = urbanized areas without a known source of SDI. Two groups were studied. Group 1 consisted of 365 subjects with asthma or allergic rhinitis and group 2 (control group) of 50 healthy individuals. Subjects from both groups were classified according to their exposure to SDI. All subjects completed standard questionnaires. Prick skin tests (STs) with an SH extract and with common allergens were performed on all subjects. Specific IgE and IgG4 to SH were measured in sera of 51 of 56 subjects from group 1 who had a positive ST to SH and in all sera from group 2.

RESULTS

Fifty-six (15.3%) subjects from group 1 and no subjects from group 2 had a positive ST to SH (wheal SH/wheal histamine >/=0.5). In group 1, positive STs to SH were 38.7%, 20.3%, and 8.2% in subjects with direct, indirect, and urban exposures, respectively (P <.001). Monosensitization to SH is absent in all subjects from group 1. The percent of subjects with positive STs to mites, pollen, and molds was highest in those with a positive ST to SH versus those with a negative ST to SH (P <.01). Asthmatic patients with a positive ST to SH, compared with those exclusively sensitized to mites, had a higher frequency of daily or weekly symptoms (59.4% vs 25.7%, respectively, P <.001) and a higher percent of glucocorticoid dependence (52.8% vs 34%, respectively, P <.01). Percent positive IgE in group 1 and group 2 were 39.2% and 10% (P <.001) and percents positive IgG4 are 27.4% and 12%, respectively (not significant). In subjects from group 1 and group 2 with direct exposure percents positive IgE are 58.3% and 13.3% (P < .001) and percents positive IgG4 were 75% and 20%, respectively (P < .02). IgG4 in group 1 was significantly higher in subjects with direct exposure compared with subjects with indirect or urban exposure.

CONCLUSION

This study demonstrated that there was (1) a high prevalence of sensitivity to SH in subjects with asthma or allergic rhinitis from Argentina and (2) an association between sensitivity to SH and severity of asthma and level of exposure to SDI.