Inclusion Criteria:

• at least a 2-year clinical history of seasonal allergic rhinitis
• allergy to a ragweed allergen, defined by positive case history and positive skin prick test
• Specific IgE for ragweed as documented by a radioallergosorbent test (RAST), or equivalent test, with class >= 2
• minimum qualifying symptom scores on at least one Symptom Diary Card during EEC exposure at both Visits 4 and 5.
• Patients must observe drug washout times listed in the protocol prior to Screening.
• Males or non-pregnant, non-lactating females who are post-menopausal or naturally or surgically sterile
• Females of childbearing potential should be using acceptable birth control methods
• Patients who are normally active and otherwise judged to be in good health
• Patients must be willing and able to give written informed consent and must provide this consent
• Patients must be willing and able to attend required study visits
• Patients must be able to follow instructions

Exclusion Criteria:

• Symptomatic for allergic rhinitis or allergic conjunctivitis from allergy to grass or trees
• Symptomatic for significant perennial rhinitis
• Concurrent disease that might complicate or interfere with investigation or evaluation of the study medications
• Concurrent use of any prohibited medication(s) or inadequate washout of medication
• Chronic or intermittent use of inhaled, oral, intramuscular, intravenous, or potent or super-potent topical corticosteroids
• Chronic use of long acting antihistamines and other concomitant medications that would affect assessment of the effectiveness of study drug(s)
• Any systemic disorder that could interfere with the evaluation of the study medication(s)
• Upper or lower respiratory infection requiring antibiotics within 14 days of the first Baseline EEC Visit
• Diagnosis of sinusitis within 30 days of the first Baseline EEC Visit
• Any ocular disorder (other than allergic conjunctivitis) which could interfere with the evaluation of the study medication
• Hypersensitivity to the study drug excipients
• active or quiescent tuberculous infection of the respiratory tract, untreated local or systemic fungal or bacterial or systemic viral infections or parasitic or ocular herpes simplex
• nasal septal ulcers, nasal surgery or nasal trauma within 90 days of enrollment
• Clinical history of anaphylaxis
• Patients with contraindications for allergy vaccines
• Clinical history of immunodeficiency, including immunosuppressant therapy
• Patients in whom tyrosine metabolism is disturbed
• Patients with contraindications to adrenaline
• Subject is taking β-blockers
• Current diagnosis of chickenpox or measles
• Clinical history of drug or alcohol abuse that would interfere with the patient’s participation in the study
• Clinical history of severe or uncontrolled cardiovascular, hepatic, renal and/or other disease/illness that could be expected to interfere with the study
• Clinical history, or evidence, of nasolacrimal drainage system malfunction
• Study site staff or immediate relatives of study site staff or other individuals who would have access to the clinical study protocol
• Patient that has received Ragweed MATAMPL in any previous clinical trial
• History of immunotherapy with ragweed pollen extract
• Patient received treatment with preparation containing MPL during the past 12 months
• Participation in any other investigational study within 30 days before entry into this study or concomitantly with this study