Dosing and uses of Grastek (Timothy grass pollen allergen extract)
Adult dosage forms and strengths
sublingual tablet
- 2800 BAU (bioequivalent allergy units)/tablet
Allergic Rhinitis
Indicated as immunotherapy for grass pollen-induced allergic rhinitis (with or without conjunctivitis) confirmed by positive skin test or in vitro testing for Timothy grass pollen-specific IgE antibodies
Initiate treatment at least 12 weeks before the expected onset of grass pollen season and maintain it throughout the season
5-65 years: 1 tablet SL qDay; give 1st dose in physician's office and observe for 30 min
>65 years: Not approved
Dosing Considerations
Not indicated for the immediate relief of allergic symptoms
Allergen contents: Timothy grass (Phleum pratense)
Administration
Instruct patients to avoid swallowing for about 1 minute following SL administration
Wash hands after handling the tablet
Do not take with food or beverage; avoid food or beverages for 5 minutes after taking the SL tablet
Pediatric dosage forms and strengths
sublingual tablet
- 2800 BAU (bioequivalent allergy units)/tablet
Allergic Rhinitis
Indicated as immunotherapy for grass pollen-induced allergic rhinitis (with or without conjunctivitis) confirmed by positive skin test or in vitro testing for Timothy grass pollen-specific IgE antibodies
Initiate treatment at least 12 weeks before the expected onset of grass pollen season and maintain it throughout the season
<5 years: Safety and efficacy not established
≥5 years: 1 tablet SL qDay; give 1st dose in physician’s office and observe for 30 min
Dosing Considerations
Not indicated for the immediate relief of allergic symptoms
Allergen contents: Timothy grass (Phleum pratense)
Administration
Administer only under adult supervision
Instruct patients to avoid swallowing for about 1 minute following SL administration
Wash hands after handling the tablet
Do not take with food or beverage; avoid food or beverages for 5 minutes after taking the SL tablet
Geriatric dosage forms and strengths
Not approved for persons older than 65 years
Grastek (Timothy grass pollen allergen extract) adverse (side) effects
>10% (Adults)
Oral pruritus (26.7%)
Throat irritation (22.5%)
Ear pruritus (12.5%)
Mouth edema (11.1%)
>10% (Children)
Oral pruritus (24.4%)
Throat irritation (21.3%)
1-10% (Adults)
Paraesthesia oral (9.8%)
Tongue pruritus (5.7%)
Lip swelling (4%)
Pharyngeal edema (3.4%)
Swollen tongue (2.8%)
Skin pruritus (2.4%)
Dyspepsia (2.3%)
Hypoesthesia oral (2.3%)
Headache (2.1%)
Nausea (1.9%)
Dry throat (1.7%)
Skin urticaria (1.7%)
Oropharyngeal pain (1.6%)
Nasal discomfort (1.6%)
Oral discomfort (1.6%)
Chest discomfort (1.6%)
Oral mucosal erythema (1.5%)
Throat tightness (1.4%)
Fatigue (1.4%)
Lip edema (1.3%)
Glossitis (1.3%)
Dyspnea (1.1%)
Stomatitis (1.1%)
Tongue disorder (1.1%)
Tongue edema (1.1%)
Glossodynia (1%)
Dysphagia (1%)
Palatal edema (1%)
1-10% (Children)
Mouth edema (9.8%)
Tongue pruritus (9.2%)
Ear pruritus (7.2%)
Lip swelling (7.2%)
Paraesthesia oral (5.4%)
Oral mucosal erythema (4.9%)
Oropharyngeal pain (4%)
Pharyngeal erythema (3.6%)
Eye pruritus (3.4%)
Headache (3.4%)
Pharyngeal edema (2.9%)
Lip pruritus (2.9%)
Cough (2.7%)
Swollen tongue (2.5%)
Dysphagia (2%)
Dyspnea (2%)
Chest discomfort (2%)
Skin urticaria (1.8%)
Nasal discomfort (1.6%)
Nasal congestion (1.6%)
Sneezing (1.6%)
Nausea (1.6%)
Oral discomfort (1.6%)
Stomatitis (1.3%)
Hypoesthesia oral (1.1%)
Glossodynia (1.1%)
Postmarketing Reports
Altered state of consciousness, drowsiness
Anaphylactic shock, angioedema, face edema, facial erythema, difficulty speaking, laryngeal discomfort, swelling of neck, throat pruritus
Asthma exercise induced, status asthmaticus, hyperventilation, forced expiratory volume decreased, oxygen saturation decreased, peak expiratory flow rate decreased, pneumonia, respiratory distress, vital capacity decreased, wheezing
Chest pressure, heart rate increased, heart rate irregular, hypotension
Diarrhea, vomiting
Dizziness
Eosinophilic esophagitis
Oral pain
Rash
Sensation of foreign body
Tremor
Warnings
Black box warnings
Can cause life-threatening allergic reactions (eg, anaphylaxis, severe laryngopharyngeal edema)
Do not administer to patients with severe, unstable, or uncontrolled asthma
Administer 1st dose in a doctor’s office and observe patient for at least 30 minutes
Patients should be prescribed autoinjectable epinephrine, trained on its appropriate use, and instructed to seek immediate medical care upon its use
May not be suitable for patients with certain underlying medical conditions that may reduce their ability to survive a serious allergic reaction (eg, markedly compromised lung function [either chronic or acute], unstable angina, recent MI, significant arrhythmia, uncontrolled hypertension)
May not be suitable for patients taking drugs that inhibit bronchodilator or epinephrine effects (eg, beta-blockers, alpha-blockers, ergot alkaloids)
Patients taking drugs that potentiate epinephrine effect (eg, TCAs, levothyroxine, MAOIs, chlorpheniramine, diphenhydramine) may be unresponsive to the usual doses of epinephrine
Carefully observe patients who receive epinephrine while taking cardiac glycosides or diuretics for the development of cardiac arrhythmias
Contraindications
Severe, unstable, or uncontrolled asthma
History of any severe systemic or local reaction to SL allergen immunotherapy
History of eosinophilic esophagitis
Hypersensitivity to inactive ingredients (gelatin, mannitol, and sodium hydroxide)
Cautions
Potential for severe allergic reaction (see Black box warnings and Contraindications)
Must be prescribed with autoinjectable epinephrine (see Black box warnings)
Can cause local reaction in the mouth or throat that could compromise the upper airway
Eosinophilic esophagitis has been reported in association with SL tablet immunotherapy
Not studied with moderate or severe asthma or any subjects who required daily medication
Withhold dose if patient experiencing an acute asthma exacerbation; re-evaluate patients with recurrent asthma exacerbations and consider discontinuing
Not studied in individuals receiving concomitant allergen immunotherapy
Stop treatment and allow complete healing of the oral cavity in patients with oral inflammation (eg, oral lichen planus, mouth ulcers or thrush) or oral wounds (eg, oral surgery, dental extraction)
Pregnancy and lactation
Pregnancy category: B
Lactation: Unknown if distributed in human breast milk; caution advised
Pregnancy categories
A: Generally acceptable. Controlled studies in pregnant women show no evidence of fetal risk.
B: May be acceptable. Either animal studies show no risk but human studies not available or animal studies showed minor risks and human studies done and showed no risk.
C: Use with caution if benefits outweigh risks. Animal studies show risk and human studies not available or neither animal nor human studies done.
D: Use in LIFE-THREATENING emergencies when no safer drug available. Positive evidence of human fetal risk.
X: Do not use in pregnancy. Risks involved outweigh potential benefits. Safer alternatives exist.
NA: Information not available.
Pharmacology of Grastek (Timothy grass pollen allergen extract)
Mechanism of action
Precise mechanism of allergen immunotherapy is not known
Allergen immunotherapy SL tablet consisting of purified and calibrated pollen extract of Timothy grass (Phleum pratense)
