Subcutaneous injections of placebo will be administered every 2 or 4 weeks along with standard of care for asthma for 60 weeks, beginning with the Randomization Visit. Dosage is dependent on participant's individual characteristics.

The number of work days missed by the caretaker due to the study participant's asthma was available for 138 of 419 (33%) study participant caretakers. Source of data: caretaker self-report. Data represent an average of those collected in the time period (weeks 12-60).

The Childhood Asthma Control Test (C-ACT) is a validated tool to assess overall asthma control (over the last 4 weeks) in patients ages 4 to 11 years. Scores can range from 0 to 27. A score of 19 or less is indicative of asthma that is not well controlled. The minimally important difference in C-ACT scores is not defined. C-ACT scores were available as an outcome measure in 236 of the 419 participants, 118 of whom were in the Omalizumab (Xolair) + Conventional Therapy arm. Data represent an average of those collected in the time period (weeks 12-60), where at least one value was available in this assessment period and at baseline for a participant.

The Asthma Control Test (ACT) is a validated tool to assess overall asthma control (over the last 4 weeks) in patients >= 12 years of age. It is a questionnaire comprised of 5 questions assessing: asthma symptoms, use of rescue medications, and the impact of asthma on everyday functioning. All questions are scored on a 5-point Likert scale, with a higher score indicating better control. All scores were added together to calculate a total score. Total scores can range from 5 to 25. A score of 19 or less is indicative of asthma that is not well controlled. The minimally important difference for ACT is 3 points. ACT scores as an outcome measure were available in 150 of the 419 participants, 77 of whom were in the Omalizumab (Xolair) + Conventional Therapy arm. Data represent an average of those collected in the time period (weeks 12-60), where at least one value was available in this assessment period and at baseline for a participant.

FEV1 is air volume exhaled in 1 second during spirometry. For the trial, mild asthma is defined as pre-bronchodilator FEV1 ≥80% predicted, requiring no/low-moderate dose of inhaled glucocorticoids; moderate asthma and severe asthma, respectively, as pre-bronchodilator FEV1 <80% predicted requiring the same glucocorticoids as mild asthma and FEV1 <80% predicted requiring high-dose inhaled glucocorticoids (with/without continuous oral glucocorticoids) or uncontrolled despite treatment. FEV1 % of predicted is FEV1 converted to a percentage of normal, based on height, weight, and race. FEV1 percent predicted data as an outcome measure were available in 363 of the 419 participants, 190 of whom were in the Omalizumab (Xolair) + Conventional Therapy arm. Data represent an average of those collected in the time period (weeks 12-60), where at least one value was available in this assessment period and at baseline for a participant.

The FEV1 (forced expiratory volume 1))/ FVC (forced vital capacity) ratio is used to evaluate airways obstructions since pure restrictive ventilatory defects cause an equal reduction in the FEV1 and the FVC. An FEV1/FVC ratio below 80% indicates airflow obstruction. Normal FEV1/FVC: 8 - 19 years of age=85%.

FEV1/FVC ratio data as an outcome measure were available in 363 of the 419 participants, 190 of whom were in the Omalizumab (Xolair) + Conventional Therapy arm. Data represent an average of those collected in the time period (weeks 12-60), where at least one value was available in this assessment period and at baseline for a participant.

Exhaled nitric oxide is a biomarker of airway inflammation. Measurement (in parts per billion,ppb) of exhaled nitric oxide (eNO) prior to spirometry, employing a technique modified after Silkoff et al (1997) and following American Thoracic Society guidelines for eNO assessment (American Thoracic Society, 1999). Nitric oxide concentrations were measured using a rapid-response chemiluminescent analyzer (NIOX™ System, Aerocrine, Sweden) which has a response time of < 700 ms for 10-90% full scale. The Food and Drug Administration has approved this device for clinical application in asthma management. Data represent an average of those collected in the time period (weeks 12-60), where at least one value was available in this assessment period and at baseline for a participant.

Adherence to the study regimen and other asthma treatments, assessed as percent of expected dose taken, by means of study interviews and study physician corroboration every 3 months. Adherence data as an outcome were available in 384 of the 419 participants, 193 of whom were in the Omalizumab (Xolair) + Conventional Therapy arm. Data represent an average of those collected in the time period (weeks 12-60), where at least one value was available in this assessment period and at baseline for a participant.

Treatment steps were established, per the National Asthma Education and Prevention Program Expert Panel Report 3 guidelines. Steps 1-2 apply to mild asthma, 3 to moderate asthma, and 4-6 to severe asthma. At Step 0, the recommendation is for no asthma-control medication or albuterol as needed; at 1, budesonide 180 mcg once a day; at 2, budesonide 180 mcg twice a day; at 3, budesonide 360 mcg twice a day; at 4, fluticasone-salmeterol (Advair, GlaxoSmithKline) 250 mcg fluticasone and 50 mcg salmeterol twice a day; at 5, Advair 250 mcg and 50 mcg twice a day plus montelukast once a day; and at 6, Advair 500 mcg and 50 mcg twice a day plus montelukast once a day. (The doses for montelukast are 5 mg per day for those <=14 years old and 10 mg per day for those >=15 years.) Data represent an average of those in the time period, where at >/= 1 value was available in this period and at baseline for a participant; results are model predicted numbers (e.g.,odds ratios converted to percentages).

Steps were established, per the National Asthma Education and Prevention Program Expert Panel Report 3 guidelines. Steps 1-2 apply to mild asthma, 3 to moderate asthma, and 4-6 to severe asthma. At Step 0, the recommendation is for no asthma-control medication or albuterol as needed; at 1, budesonide 180 mcg once a day; at 2, budesonide 180 mcg twice a day; at 3, budesonide 360 mcg twice a day; at 4, fluticasone-salmeterol (Advair, GlaxoSmithKline) 250 mcg fluticasone and 50 mcg salmeterol twice a day; at 5, Advair 250 mcg and 50 mcg twice a day plus montelukast once a day; and at 6, Advair 500 mcg and 50 mcg twice a day plus montelukast once a day. (The doses for montelukast are 5 mg per day for those <=14 years old and 10 mg per day for those >=15 years.) Data represent an average of those in the time period, where at least one value was available in this period and at baseline for a participant. Results values are model predicted numbers,(e.g, odds ratios converted to percentages).

Prescribed dose (mcg/day) of inhaled glucocorticoids to maintain asthma control. The dose of inhaled glucocorticoids was converted to the budesonide-equivalent dose. Data represent an average of those collected in the time period (weeks 12-60), where at least one value was available in this assessment period and at baseline for a participant.

Percent of participants prescribed long-acting beta 2 agonists to maintain asthma control. Data represent an average of those collected in the time period (weeks 12-60), where at least one value was available in this assessment period and at baseline for a participant. Results values are model predicted numbers, (e.g.,odds ratios converted to percentages).

Percent participants with >=1 hospitalizations. A hospitalization is defined as an asthma-related, overnight hospitalization. . Results values are model predicted numbers,(e.g., odds ratios converted to percentages).

Percent participants with >=1 exacerbations. An exacerbation was defined as a prednisone burst (a minimum of 20 mg per day of prednisone, or the equivalent, taken for any 3 of 5 consecutive days) or hospitalization. Results values are model predicted numbers, (e.g.,odds ratios converted to percentages).

Asthma-Specific Quality of Life (QOL) Measure . The PACQLQ is a validated tool that measures limitations and anxieties faced by primary caregivers of children with asthma. Scores are calculated as the mean score within two domains of questions (re: activity limitation and emotional function) and overall scores represent the mean across all questions. The use of the PACQLQ is valid for use in the caretakers of children ages 7 to 17 years of age. Higher scores indicate better quality of life. Minimum possible score is 1 (maximum impairment); maximum possible score is 7 (no impairment). The range of actual scores were a minimum of 2.4 and a maximum of 7.

Method: Caretaker self-report. PACQLQ scores were available for 320 of 419 (76%) of study participant caretakers (159 in the Omalizumab (Xolair) + Conventional Therapy arm).

Asthma-specific quality of life (QOL) validated tool designed for children 7 to 17 years of age. PAQLQ measures functional problems that are most troublesome to children with asthma. PAQLQ has 23 questions in 3 domains (activity limitation=5, emotional function=8, symptoms=10). Patients responded to each question on a 7-point Likert scale. Overall PAQLQ score is mean of 23 questions; each domain score is mean of questions in that domain. Minimum possible score is 1 (maximum impairment); maximum possible score is 7 (no impairment). Actual scores ranged from 2.1 to 7.

PAQLQ scores were available for 338 of 419 (81%) of study participants, 170 of whom were in the Omalizumab (Xolair) + Conventional Therapy arm.

ImmPort study identifier is SDY211.

ImmPort study identifier is SDY211.

Placebo was administered subcutaneously every 2 or 4 weeks over a period of 60 weeks to participants classified as having moderate to severe asthma. Doses (mg) and dosing frequency were determined by serum total IgE level (IU/mL) and body weight (kg). Also, participants continued with their conventional asthma therapy according to the National Asthma Education and Prevention Program (NAEPP-II, 2002) guidelines, under the management of an asthma specialist health care provider.

Total of all reporting groups

Asthma duration is the number of years since the participant was told by a physician that he/she has asthma, based upon the caretaker's response as reported at the baseline visit. This data was available for 332 of 419 (79%) study participants. Of the 332, 169 were from the Omalizumab (Xolair) + Conventional Therapy arm.

The Childhood Asthma Control Test (C-ACT) is a validated tool to assess overall asthma control (over the last 4 weeks) in patients ages 4 to 11 years. Scores can range from 0 to 27. A score of 19 or less is indicative of asthma that is not well controlled. The minimally important difference in C-ACT scores is not defined. C-ACT scores were available and relevant for 253 of 419 (60%) study participants. Of the 253, 123 were from the Omalizumab (Xolair) + Conventional Therapy arm.

The Asthma Control Test (ACT) is a validated tool to assess asthma control (over the last 4 weeks) in patients >= 12 yrs old. It is comprised of 5 questions assessing symptoms, use of rescue medications, and the impact of asthma on everyday functioning. All questions are scored on a 5-point Likert scale (higher score indicating better control). Total scores can range from 5-25. A score of <= 19 is indicative of not well-controlled asthma. The minimally important difference is 3 points. Scores were available for 166 of 419 participants (85 from the Omalizumab + Conventional Therapy arm).

Maximum symptom days was calculated as the largest of the following variables at the baseline visit: number of days with wheezing, chest tightness, or cough; number of nights of sleep disturbance; and number of days when activities were affected. This symptom scale ranges from 0 to 14 days per a 2-week look-back period. A higher score reflected a greater number of asthma symptoms.

The number of school days missed reported by the participant's caretaker was available for 339 of the 419 (81%) study participants. Of the 339, 164 were enrolled in the Omalizumab (Xolair) + Conventional Therapy arm.

FEV1 is air volume exhaled in 1 second during spirometry. For the trial, mild asthma is defined as pre-bronchodilator FEV1 ≥80% predicted, requiring no/low-moderate dose of inhaled glucocorticoids; moderate asthma and severe asthma, respectively, as pre-bronchodilator FEV1 <80% predicted requiring the same glucocorticoids as mild asthma and FEV1 <80% predicted requiring high-dose inhaled glucocorticoids (with/without continuous oral glucocorticoids) or uncontrolled despite treatment. FEV1 % of predicted is FEV1 converted to a percentage of normal, based on height, weight, and race.

The FEV1 (forced expiratory volume 1))/ FVC (forced vital capacity) ratio is used to evaluate airways obstructions since pure restrictive ventilatory defects cause an equal reduction in the FEV1 and the FVC. An FEV1/FVC ratio below 80% indicates airflow obstruction. Normal FEV1/FVC: 8 - 19 years of age=85%.

Baseline FEV1/FVC ratio and FEV1 percent predicted data were available in 398 of the 419 participants. Of the 398, 204 were enrolled in the Omalizumab (Xolair) + Conventional Therapy arm.

Placebo was administered subcutaneously every 2 or 4 weeks over a period of 60 weeks to participants classified as having moderate to severe asthma. Doses (mg) and dosing frequency were determined by serum total IgE level (IU/mL) and body weight (kg). Also, participants continued with their conventional asthma therapy according to the National Asthma Education and Prevention Program (NAEPP-II, 2002) guidelines, under the management of an asthma specialist health care provider.

The number of school days missed was available for 307 of the 419 (73%) study participants, of which 152 were in the Omalizumab (Xolair) + Conventional Therapy arm. Source of data: caretaker/participant self-report. Data represent an average of those collected in the time period (weeks 12-60), where at least one value was available in this assessment period and at baseline for a participant.

Intent-to-treat

The number of work days missed by the caretaker due to the study participant's asthma was available for 138 of 419 (33%) study participant caretakers. Source of data: caretaker self-report. Data represent an average of those collected in the time period (weeks 12-60).

Intent-to-treat

The Childhood Asthma Control Test (C-ACT) is a validated tool to assess overall asthma control (over the last 4 weeks) in patients ages 4 to 11 years. Scores can range from 0 to 27. A score of 19 or less is indicative of asthma that is not well controlled. The minimally important difference in C-ACT scores is not defined. C-ACT scores were available as an outcome measure in 236 of the 419 participants, 118 of whom were in the Omalizumab (Xolair) + Conventional Therapy arm. Data represent an average of those collected in the time period (weeks 12-60), where at least one value was available in this assessment period and at baseline for a participant.

Intent-to-treat

The Asthma Control Test (ACT) is a validated tool to assess overall asthma control (over the last 4 weeks) in patients >= 12 years of age. It is a questionnaire comprised of 5 questions assessing: asthma symptoms, use of rescue medications, and the impact of asthma on everyday functioning. All questions are scored on a 5-point Likert scale, with a higher score indicating better control. All scores were added together to calculate a total score. Total scores can range from 5 to 25. A score of 19 or less is indicative of asthma that is not well controlled. The minimally important difference for ACT is 3 points. ACT scores as an outcome measure were available in 150 of the 419 participants, 77 of whom were in the Omalizumab (Xolair) + Conventional Therapy arm. Data represent an average of those collected in the time period (weeks 12-60), where at least one value was available in this assessment period and at baseline for a participant.

Intent-to-treat

FEV1 is air volume exhaled in 1 second during spirometry. For the trial, mild asthma is defined as pre-bronchodilator FEV1 ≥80% predicted, requiring no/low-moderate dose of inhaled glucocorticoids; moderate asthma and severe asthma, respectively, as pre-bronchodilator FEV1 <80% predicted requiring the same glucocorticoids as mild asthma and FEV1 <80% predicted requiring high-dose inhaled glucocorticoids (with/without continuous oral glucocorticoids) or uncontrolled despite treatment. FEV1 % of predicted is FEV1 converted to a percentage of normal, based on height, weight, and race. FEV1 percent predicted data as an outcome measure were available in 363 of the 419 participants, 190 of whom were in the Omalizumab (Xolair) + Conventional Therapy arm. Data represent an average of those collected in the time period (weeks 12-60), where at least one value was available in this assessment period and at baseline for a participant.

Intent-to-treat

The FEV1 (forced expiratory volume 1))/ FVC (forced vital capacity) ratio is used to evaluate airways obstructions since pure restrictive ventilatory defects cause an equal reduction in the FEV1 and the FVC. An FEV1/FVC ratio below 80% indicates airflow obstruction. Normal FEV1/FVC: 8 - 19 years of age=85%.

FEV1/FVC ratio data as an outcome measure were available in 363 of the 419 participants, 190 of whom were in the Omalizumab (Xolair) + Conventional Therapy arm. Data represent an average of those collected in the time period (weeks 12-60), where at least one value was available in this assessment period and at baseline for a participant.

Intent-to-treat

Exhaled nitric oxide is a biomarker of airway inflammation. Measurement (in parts per billion,ppb) of exhaled nitric oxide (eNO) prior to spirometry, employing a technique modified after Silkoff et al (1997) and following American Thoracic Society guidelines for eNO assessment (American Thoracic Society, 1999). Nitric oxide concentrations were measured using a rapid-response chemiluminescent analyzer (NIOX™ System, Aerocrine, Sweden) which has a response time of < 700 ms for 10-90% full scale. The Food and Drug Administration has approved this device for clinical application in asthma management. Data represent an average of those collected in the time period (weeks 12-60), where at least one value was available in this assessment period and at baseline for a participant.

Intent-to-treat

Adherence to the study regimen and other asthma treatments, assessed as percent of expected dose taken, by means of study interviews and study physician corroboration every 3 months. Adherence data as an outcome were available in 384 of the 419 participants, 193 of whom were in the Omalizumab (Xolair) + Conventional Therapy arm. Data represent an average of those collected in the time period (weeks 12-60), where at least one value was available in this assessment period and at baseline for a participant.

Intent-to-treat

Treatment steps were established, per the National Asthma Education and Prevention Program Expert Panel Report 3 guidelines. Steps 1-2 apply to mild asthma, 3 to moderate asthma, and 4-6 to severe asthma. At Step 0, the recommendation is for no asthma-control medication or albuterol as needed; at 1, budesonide 180 mcg once a day; at 2, budesonide 180 mcg twice a day; at 3, budesonide 360 mcg twice a day; at 4, fluticasone-salmeterol (Advair, GlaxoSmithKline) 250 mcg fluticasone and 50 mcg salmeterol twice a day; at 5, Advair 250 mcg and 50 mcg twice a day plus montelukast once a day; and at 6, Advair 500 mcg and 50 mcg twice a day plus montelukast once a day. (The doses for montelukast are 5 mg per day for those <=14 years old and 10 mg per day for those >=15 years.) Data represent an average of those in the time period, where at >/= 1 value was available in this period and at baseline for a participant; results are model predicted numbers (e.g.,odds ratios converted to percentages).

Intent-to-treat

Steps were established, per the National Asthma Education and Prevention Program Expert Panel Report 3 guidelines. Steps 1-2 apply to mild asthma, 3 to moderate asthma, and 4-6 to severe asthma. At Step 0, the recommendation is for no asthma-control medication or albuterol as needed; at 1, budesonide 180 mcg once a day; at 2, budesonide 180 mcg twice a day; at 3, budesonide 360 mcg twice a day; at 4, fluticasone-salmeterol (Advair, GlaxoSmithKline) 250 mcg fluticasone and 50 mcg salmeterol twice a day; at 5, Advair 250 mcg and 50 mcg twice a day plus montelukast once a day; and at 6, Advair 500 mcg and 50 mcg twice a day plus montelukast once a day. (The doses for montelukast are 5 mg per day for those <=14 years old and 10 mg per day for those >=15 years.) Data represent an average of those in the time period, where at least one value was available in this period and at baseline for a participant. Results values are model predicted numbers,(e.g, odds ratios converted to percentages).

Intent-to-treat

Prescribed dose (mcg/day) of inhaled glucocorticoids to maintain asthma control. The dose of inhaled glucocorticoids was converted to the budesonide-equivalent dose. Data represent an average of those collected in the time period (weeks 12-60), where at least one value was available in this assessment period and at baseline for a participant.

Intent-to-treat

Percent of participants prescribed long-acting beta 2 agonists to maintain asthma control. Data represent an average of those collected in the time period (weeks 12-60), where at least one value was available in this assessment period and at baseline for a participant. Results values are model predicted numbers, (e.g.,odds ratios converted to percentages).

Intent-to-treat

Percent participants with >=1 hospitalizations. A hospitalization is defined as an asthma-related, overnight hospitalization. . Results values are model predicted numbers,(e.g., odds ratios converted to percentages).

Intent-to-treat

Percent participants with >=1 exacerbations. An exacerbation was defined as a prednisone burst (a minimum of 20 mg per day of prednisone, or the equivalent, taken for any 3 of 5 consecutive days) or hospitalization. Results values are model predicted numbers, (e.g.,odds ratios converted to percentages).

Intent-to-treat

Asthma-Specific Quality of Life (QOL) Measure . The PACQLQ is a validated tool that measures limitations and anxieties faced by primary caregivers of children with asthma. Scores are calculated as the mean score within two domains of questions (re: activity limitation and emotional function) and overall scores represent the mean across all questions. The use of the PACQLQ is valid for use in the caretakers of children ages 7 to 17 years of age. Higher scores indicate better quality of life. Minimum possible score is 1 (maximum impairment); maximum possible score is 7 (no impairment). The range of actual scores were a minimum of 2.4 and a maximum of 7.

Method: Caretaker self-report. PACQLQ scores were available for 320 of 419 (76%) of study participant caretakers (159 in the Omalizumab (Xolair) + Conventional Therapy arm).

Intent-to-treat

Asthma-specific quality of life (QOL) validated tool designed for children 7 to 17 years of age. PAQLQ measures functional problems that are most troublesome to children with asthma. PAQLQ has 23 questions in 3 domains (activity limitation=5, emotional function=8, symptoms=10). Patients responded to each question on a 7-point Likert scale. Overall PAQLQ score is mean of 23 questions; each domain score is mean of questions in that domain. Minimum possible score is 1 (maximum impairment); maximum possible score is 7 (no impairment). Actual scores ranged from 2.1 to 7.

PAQLQ scores were available for 338 of 419 (81%) of study participants, 170 of whom were in the Omalizumab (Xolair) + Conventional Therapy arm.

Intent-to-treat

Placebo was administered subcutaneously every 2 or 4 weeks over a period of 60 weeks to participants classified as having moderate to severe asthma. Doses (mg) and dosing frequency were determined by serum total IgE level (IU/mL) and body weight (kg). Also, participants continued with their conventional asthma therapy according to the National Asthma Education and Prevention Program (NAEPP-II, 2002) guidelines, under the management of an asthma specialist health care provider.