Grastek tablets are derived from Timothy grass pollen. Grastek tablets are used sublingually to treat patients with allergic rhinitis and conjunctivitis (or without conjunctivitis) caused by an allergic reaction to grass pollen. The allergy is either confirmed by a positive skin test or in vitro testing by the development of IgE to Timothy grass or cross-reactive grass pollens.

Timothy grass pollen (Grastek Tablets) Uses:

• Grass pollen-induced allergic rhinitis:

  • Used as an immunotherapy to treat allergic rhinitis caused by grass pollen in patients aged 5 to 65 years old, with or without conjunctivitis, and validated by a positive skin test or in vitro testing for pollen-specific IgE antibodies for Timothy grass or cross-reactive grass pollens. Not to be used to treat allergy symptoms right away.

Timothy grass pollen (Grastek Tablets) Dose in Adults

Note:

• Dosage strength expressed in Bioequivalent Allergy Units (BAU). Note: The treatment should be started ≥12 weeks before the expected onset of each pollen season and continued throughout the pollen season.
• May take daily for 3 years consecutively (including intervals between grass pollen seasons). No Safety and efficacy have been established of initiating treatment during the ragweed pollen season.
• In clinical trials, treatment pauses of up to one week were permitted; however, there is little information available regarding restarting therapy after missing a dose.

Dose for treating Grass pollen-induced allergic rhinitis:

• Adults ≤65 years:

  • Sublingual: 1 tablet (2,800 BAU) once a day

Timothy grass pollen (Grastek Tablets) Dose in Children

Note:

• Dosage strength expressed in Bioequivalent Allergy Units (BAU). The treatment should be started ≥12 weeks before the expected onset of each pollen season and continued throughout the pollen season.
• May take daily for 3 years consecutively (including intervals between grass pollen seasons). No Safety and efficacy have been established of initiating treatment during the ragweed pollen season.
• In clinical trials, treatment pauses of up to one week were permitted; however, there is little information available regarding restarting therapy after missing a dose.

Timothy grass pollen (Grastek Tablets) Dose in the treatment of Grass pollen-induced allergic rhinitis:

• Children ≥5 years and Adolescents:

  • Sublingual: One tablet (2,800 BAU) once a day. Administer the 1st dose in a health care setting as there is a potential for allergic reactions.

Pregnancy Risk Factor B

• Animal reproduction studies have not shown any adverse effects.

Use during breastfeeding:

• It is unknown if breast milk contains grass pollen allergen extract.
• Follow the manufacturer's instructions. Nursing women should be treated with caution

Dose in Kidney Disease:

No dosage adjustments provided in the manufacturer’s labeling.

Dose in Liver disease:

No dosage adjustments provided in the manufacturer’s labeling.

Common Side Effects of Timothy grass pollen (Grastek Tablets):

• Dermatologic:

  • Pruritus of ear

• Gastrointestinal:

  • Oral itching

• Hypersensitivity:

  • Mouth edema

• Respiratory:

  • Throat irritation

Less Common Side Effects of Timothy grass pollen:

• Cardiovascular:

  • Chest Discomfort
  • Lip Edema

• Central Nervous System:

  • Headache
  • Oral Hypoesthesia
  • Fatigue

• Dermatologic:

  • Tongue Pruritus
  • Lip Pruritus
  • Pruritus
  • Urticaria

• Endocrine & Metabolic:

  • Palatal Edema

• Gastrointestinal:

  • Oral Paresthesia
  • Lip Swelling
  • Oral Mucosa Erythema
  • Swollen Tongue
  • Dyspepsia
  • Nausea
  • Oral Discomfort
  • Dysphagia
  • Glossalgia
  • Glossitis
  • Stomatitis
  • Tongue Disease
  • Abdominal Pain
  • Gastroesophageal Reflux Disease

• Ophthalmic:

  • Eye Pruritus

• Respiratory:

  • Pharyngeal Erythema
  • Oropharyngeal Pain
  • Cough
  • Pharyngeal Edema
  • Dry Throat
  • Nasal Congestion
  • Nasal Discomfort
  • Sneezing
  • Dyspnea
  • Constriction Of The Pharynx

Contraindications to Timothy grass pollen (Grastek Tablets):

• Hypersensitivity to any inactive ingredients (mannitol or gelatin) in this product, or any other component of its formulation.
• Asthma (severe or unstable asthma)
• Significant local or allergic reactions to sublingual allergen immunotherapy in the past
• An earlier history of eosinophilic esophagitis

Canadian labeling: Additional contraindications not in US labeling

• FEV1 70% (unstable, severe, chronic, or severe seasonal asthma)
• Combination therapy with beta-blockers
• Oral inflammation (eg, oral lichen planus, oral ulcerations, severe oral candidiasis, or dental extraction).

Warnings and precautions

• Esophagitis:

  • Eosinophilic reflux may be caused by sublingual tablet immunotherapy. 
  • Patients with persistent or severe gastroesophageal symptoms (eg dysphagia, chest discomfort) should stop receiving therapy.
  • Therapy is not recommended for patients with eosinophilic esophagitis.

• Hypersensitivity reactions: [US Boxed Warning]

  • This could result in severe laryngopharyngeal limitations or life-threatening allergic reactions like anaphylaxis.
  • Local responses could happen in the mouth or throat.
  • It should be suggested that patients refrain from using this medication if they experience frequent and worsening side effects in the mouth or throat.
  • The risk of harmful local or systemic effects may rise when allergen immunotherapy is used concurrently.

• Respiratory disease: [US-Boxed Warning]

  • Patients with severe, unstable or uncontrolled asthma should not be given this medication. There are no studies on patients with moderate and severe asthma.
  • Do not treat acute asthma exacerbations.
  • Recurrent asthma exacerbations should be evaluated and the patient should be re-evaluated.
  • Recurrent asthma exacerbations should be considered when considering treatment discontinuation.
  • The contraindication to the use of asthma medication is uncontrolled or unstable asthma.

Monitoring parameters:

• Signs/symptoms of hypersensitivity
• Monitoring should be done for at least 30 minutes after giving the 1st dose.

How to administer Timothy grass pollen (Grastek Tablets)?

Sublingual:

• The 1st dose should be given in a healthcare setting as there is a potential for allergic reactions; monitoring should be done for at least 30 minutes after giving the 1st dose & may give subsequent doses at home if well tolerated by the patient.
• With dry hands, the sublingual tablet may be removed from the blister immediately before administration.
• Before consuming, the pill needs to be placed under the tongue and allowed to dissolve completely.
• After handling the tablet, wash your hands. Following administration, you should wait five minutes before eating or drinking anything.
• Make auto-injectable epinephrine available to patients

Mechanism of action of Timothy grass pollen (Grastek Tablets):

• The grass pollen allergen extract includes an extract from timothygrass. 
• Although the mechanism of action is still unclear, it has been suggested that specific immunotherapy (SIT), may induce a switch between T helper 2 and T helper 1 cells (Th2) responses.
• This results in a decrease of interleukin-4 and interleukin-5, respectively, and an increase in interleukin-10, (IL-10). IgG-blocking antibody production that competes with IgE antibodies for allergen-binding, proliferation of regulatory T lymphocytes, cytokines and eosinophils, as well as a decrease in mast cells and eosinophils.

International Brand Names of Timothy grass pollen:

• Grastek

Timothy grass pollen Brand Names in Pakistan:

No Brands Available in Pakistan.