• Healthy male and female subjects in good health as determined by past medical history, physical examination, vital signs, electrocardiogram, and laboratory tests at screening.
CSU and CINDU patients (cold and cholinergic urticaria) CSU patients
Diagnosis of CSU (acc. to criteria defined in Zuberbier et al 2018) not adequately controlled with H1-AH at approved doses alone at the time of randomization, as defined by all of the following:
UAS7 score (range 0-42) ≥ 16 and HSS7 (range 0-21) ≥ 8 during 7 days prior to randomization
CSU for ≥ 6 months CINDU patients (cold and cholinergic urticaria)
For patients with cold urticaria: Cold urticaria symptoms persisting for at least 6 months prior to study enrollment and a positive cold urticaria provocation test defined as wheal response to TempTest 4.0® at Day 1.
For patients with cholinergic urticaria: Cholinergic urticaria symptoms for at least 6 months prior to enrollment and a positive response in the challenge test defined as a wheal response in the pulse controlled ergometry provocation test (30 minutes bicycle challenge).
History of allergies or allergy to the challenge substances including ciprofloxacin, icatibant, other quinolones or excipients of the substances being used in the study.
Recent (within the last three years) and/or recurrent history of autonomic dysfunction (e.g. recurrent episodes of fainting, palpitations, etc.).
Donation or loss of 450 mL or more blood within eight weeks prior to initial dosing, or longer if required by local regulations.
CSU and CINDU patients (cold and cholinergic urticaria)
History of allergies or allergy to the challenge substances including ciprofloxacin, icatibant, other quinolones or excipients of the substances being used in this study.
Contraindications to or hypersensitivity to antihistamines (such as fexofenadine, loratadine, cetirizine, rupatadine, bilastine) or epinephrine or any of the ingredients.
History or presence of renal disease and/or estimated glomerular filtration (eGFR) rate of < 35 mL/min as calculated by the CKD-EPI formula at Screening.
For subjects who enter Part 2: Patients with a history of or a risk of parasite infections (recent stay in tropical/subtropical areas with low hygiene standards). To allow enrollment of a patient at risk perform stool examinations for ova or parasites and demonstrate absence of infection first.
Diseases with possible signs and symptoms of urticaria or angioedema such as urticarial vasculitis, erythema multiforme, cutaneous mastocytosis (urticaria pigmentosa), and hereditary or acquired angioedema (e.g. due to C1 inhibitor deficiency).
Clearly defined underlying etiology for chronic urticaria symptoms other than CSU. This includes the following:
CSU patients should not have inducible urticaria forms impacting their daily symptoms in a relevant way, such as but not limited to urticaria factitia, cold-, heat-, solar-, pressure-, delayed pressure, aquagenic-, cholinergic-, or contact-urticaria.
CINDU patients (cold and cholinergic urticaria)
Clearly defined underlying etiology for chronic urticaria symptoms other than CINDU. This includes the following:
CINDU patients should not have spontaneous urticaria impacting their symptoms in a relevant way.
Other protocol-defined inclusion/exclusion criteria may apply .