Most Serious and/or Most Frequently Observed Adverse Reactions:

• Hypoglycemia [see WARNINGS AND PRECAUTIONS, ADVERSE REACTIONS]
• Hypersensitivity and Allergic Reactions, including Anaphylaxis [see CONTRAINDICATIONS, WARNINGS AND PRECAUTIONS, ADVERSE REACTIONS]
• Intracranial hypertension (IH) [see WARNINGS AND PRECAUTIONS, ADVERSE REACTIONS]
• Tonsillar and Adenoidal Hypertrophy and related complications [see WARNINGS AND PRECAUTIONS, ADVERSE REACTIONS]

Clinical Trial Experience

Because clinical trials are conducted under widely varying conditions, adverse reaction rates observed in the clinical trials of a drug cannot be directly compared to rates in the clinical trials of another drug and may not reflect the rates observed in practice.

In clinical studies of 71 subjects with Primary IGFD treated for a mean duration of 3.9 years and representing 274 subject-years, no subjects withdrew from any clinical study because of adverse reactions. Adverse reactions to INCRELEX® treatment that occurred in 5% or more of these study participants are listed below by organ class.

Metabolism and Nutrition Disorders: hypoglycemia

General Disorders and Administrative Site Conditions: lipohypertrophy, bruising

Infections and Infestations: otitis media, serous otitis media

Respiratory, Thoracic and Mediastinal Disorders: snoring, tonsillar hypertrophy

Nervous System Disorders: headache, dizziness, convulsions

Gastrointestinal Disorders: vomiting

Ear and Labyrinth Disorders: hypoacusis, fluid in middle ear, ear pain, abnormal tympanometry

Cardiac Disorders: cardiac murmur

Musculoskeletal and Connective Tissue Disorders: arthralgia, pain in extremity

Blood and Lymphatic System Disorders: thymus hypertrophy

Surgical and Medical Procedures: ear tube insertion

Hypoglycemia was reported by 30 subjects (42%) at least once during their course of therapy. Most cases of hypoglycemia were mild or moderate in severity. Five subjects had severe hypoglycemia (requiring assistance and treatment) on one or more occasion and 4 subjects experienced hypoglycemic seizures/loss of consciousness on one or more occasion. Of the 30 subjects reporting hypoglycemia, 14 (47%) had a history of hypoglycemia prior to treatment. The frequency of hypoglycemia was highest in the first month of treatment, and episodes were more frequent in younger children. Symptomatic hypoglycemia was generally avoided when a meal or snack was consumed either shortly (i.e., 20 minutes) before or after the administration of INCRELEX®.

Tonsillar hypertrophy was noted in 11 (15%) subjects in the first 1 to 2 years of therapy with lesser tonsillar growth in subsequent years. Tonsillectomy or tonsillectomy/adenoidectomy was performed in 7 subjects; 3 of these had obstructive sleep apnea, which resolved after the procedure in all three cases.

Intracranial hypertension occurred in three subjects. In two subjects the events resolved without interruption of INCRELEX® treatment. INCRELEX® treatment was discontinued in the third subject and resumed later at a lower dose without recurrence.

Mild elevations in the serum AST and LDH were found in a significant proportion of patients before and during treatment. Rise in levels of these serum enzymes did not lead to treatment discontinuation. ALT elevations were occasionally noted during treatment.

Renal and splenic lengths (measured by ultrasound) increased rapidly on INCRELEX® treatment during the first years of therapy. This lengthening slowed down subsequently; though in some patients, renal and/or splenic length reached or surpassed the 95th percentile. Renal function (as defined by serum creatinine and calculated creatinine clearance) was normal in all patients, irrespective of renal growth.

Elevations in cholesterol and triglycerides to above the upper limit of normal were observed before and during treatment.

Echocardiographic evidence of cardiomegaly/valvulopathy was observed in a few individuals without associated clinical symptoms. The relation of these cardiac changes to drug treatment cannot be assessed due to underlying disease and the lack of a control group.

Thickening of the soft tissues of the face was observed in several patients and should be monitored during INCRELEX® treatment.

As with all therapeutic proteins, there is potential for immunogenicity. Anti-IGF-1 antibodies were present at one or more of the periodic assessments in 14 of 23 children with Primary IGFD treated for 2 years. However, no clinical consequences of these antibodies were observed (e.g., attenuation of growth). The detection of antibody formation is highly dependent on the sensitivity and specificity of the assay. Additionally, the observed incidence of antibody (including neutralizing antibody) positivity in an assay may be influenced by several factors including assay methodology, sample handling, timing of sample collection, concomitant medications, and underlying disease. For these reasons, comparison of the incidence of antibodies to INCRELEX® with the incidence of antibodies to other products may be misleading.

Post-Marketing Experience

The following adverse reactions have been identified during post approval use of INCRELEX®. Because these reactions are reported voluntarily from a population of uncertain size, it is not always possible to reliably estimate their frequency or establish a causal relationship to drug exposure.

Systemic hypersensitivity; anaphylaxis, generalized urticaria, angioedema, dyspnea

In the post-marketing setting, the frequency of cases indicative of anaphylaxis was estimated to be 0.3%. Symptoms included hives, angioedema, and dyspnea, and some patients required hospitalization. Upon re-administration, symptoms did not re-occur in all patients.

Local allergic reactions at the injection site; pruritis, urticaria.

Skin and Subcutaneous Tissue Disorders: alopecia, hair texture abnormal.

Last reviewed on RxList: 9/21/2012
This monograph has been modified to include the generic and brand name in many instances.