The RSS system is a 10-point radiographic scoring method that was developed to assess the severity of nutritional rickets in the wrists and knees based on the degree of metaphyseal fraying, cupping, and the proportion of the growth plate affected. Scores are assigned for the unilateral wrist and knee X-rays deemed by the rater to be the more severe of the bilateral images. The maximum total score on the RSS is 10 points and the minimum score is 0, with a total possible score of 4 points for the wrists and 6 points for the knees. Higher scores indicate greater rickets severity.

Intent to Treat (ITT) Analysis Set: all participants who received at least 1 dose of study therapy and had at least 1 post-dose measurement at given time point.

Pharmacokinetic/Pharamcodynamic (PK/PD) Analysis Set: all participants who received at least 1 dose of therapy and had evaluable serum data at given time point.

PK/PD Analysis Set: all participants who received at least 1 dose of therapy and had evaluable serum data at given time point.

Data for urinary phosphorus and TRP were used in calculation TmP/GFR.

PK/PD Analysis Set: all participants who received at least 1 dose of therapy and had evaluable serum data at given time point.

The RSS system is a 10-point radiographic scoring method that was developed to assess the severity of nutritional rickets in the wrists and knees based on the degree of metaphyseal fraying, cupping, and the proportion of the growth plate affected. Scores are assigned for the unilateral wrist and knee X-rays deemed by the rater to be the more severe of the bilateral images. The maximum total score on the RSS is 10 points and the minimum score is 0, with a total possible score of 4 points for the wrists and 6 points for the knees. Higher scores indicate greater rickets severity.

ITT Analysis Set: all participants who received at least 1 dose of study therapy and had at least 1 post-dose measurement at given time point.

The RSS system is a 10-point radiographic scoring method that was developed to assess the severity of nutritional rickets in the wrists and knees based on the degree of metaphyseal fraying, cupping, and the proportion of the growth plate affected. Scores are assigned for the unilateral wrist and knee X-rays deemed by the rater to be the more severe of the bilateral images. The maximum total score on the RSS is 10 points and the minimum score is 0, with a total possible score of 4 points for the wrists and 6 points for the knees. Higher scores indicate greater rickets severity.

ITT Analysis Set: all participants who received at least 1 dose of study therapy and had at least 1 post-dose measurement at given time point.

Changes in the severity of rickets and bowing were assessed centrally by three independent pediatric radiologists contracted by a central imaging facility using a disease specific qualitative RGI-C scoring system. The RGI-C is a seven point ordinal scale with possible values: +3 = very much better (complete or near complete healing of rickets), +2 = much better (substantial healing of rickets), +1 = minimally better (i.e., minimal healing of rickets), 0 = unchanged, -1 = minimally worse (minimal worsening of rickets), -2 = much worse (moderate worsening of rickets), -3 = very much worse (severe worsening of rickets).

ITT Analysis Set: all participants who received at least 1 dose of study therapy and had at least 1 post-dose measurement at given time point.

Changes in the severity of rickets and bowing were assessed centrally by three independent pediatric radiologists contracted by a central imaging facility using a disease specific qualitative RGI-C scoring system. The RGI-C is a seven point ordinal scale with possible values: +3 = very much better (complete or near complete healing of rickets), +2 = much better (substantial healing of rickets), +1 = minimally better (i.e., minimal healing of rickets), 0 = unchanged, -1 = minimally worse (minimal worsening of rickets), -2 = much worse (moderate worsening of rickets), -3 = very much worse (severe worsening of rickets).

ITT Analysis Set: all participants who received at least 1 dose of study therapy and had at least 1 post-dose measurement at given time point.

Changes in the severity of rickets and bowing were assessed centrally by three independent pediatric radiologists contracted by a central imaging facility using a disease specific qualitative RGI-C scoring system. The RGI-C is a seven point ordinal scale with possible values: +3 = very much better (complete or near complete healing of rickets), +2 = much better (substantial healing of rickets), +1 = minimally better (i.e., minimal healing of rickets), 0 = unchanged, -1 = minimally worse (minimal worsening of rickets), -2 = much worse (moderate worsening of rickets), -3 = very much worse (severe worsening of rickets).

ITT Analysis Set: all participants who received at least 1 dose of study therapy and had at least 1 post-dose measurement at given time point.

ITT Analysis Set: all participants who received at least 1 dose of study therapy and had at least 1 post-dose measurement at given time point.

Standing height Z scores are measures of height adjusted for a child's age and sex. The Z score indicates the number of standard deviations away from a reference population (from the CDC growth charts) in the same age range and with the same sex. A Z score of 0 is equal to the mean with negative numbers indicating values lower than the mean and positive values higher. Higher Z scores indicate a better outcome.

ITT Analysis Set: all participants who received at least 1 dose of study therapy and had at least 1 post-dose measurement at given time point.

ITT Analysis Set: all participants who received at least 1 dose of study therapy and had at least 1 post-dose measurement at given time point.

ITT Analysis Set: all participants who received at least 1 dose of study therapy and had at least 1 post-dose measurement at given time point.

ITT Analysis Set: all participants who received at least 1 dose of study therapy and had at least 1 post-dose measurement at given time point.

ITT Analysis Set: all participants who received at least 1 dose of study therapy and had at least 1 post-dose measurement at given time point.

The total distance walked (meters) in a 6-minute period was measured. The percent of predicted values were calculated using published normative data based on age, gender, and height (Geiger et al. 2007).

ITT Analysis Set: all participants who received at least 1 dose of study therapy and had at least 1 post-dose measurement at given time point.

The POSNA-PODCI yields 4 functional assessment scores: Upper Extremity Function,Transfers and Basic Mobility, Sports and Physical Function, and Comfort/Pain. In addition, a Global Function score, which is an average of the 4 functional assessments, and a Happiness score are calculated. Raw, mean, standardized, and normative scores are calculated for each scale. Normative scores are calculated so that higher scores indicate better functioning. All scores are referenced to the general, healthy population with a normative mean score of 50 and a standard deviation of 10.

ITT Analysis Set: all participants who received at least 1 dose of study therapy and had at least 1 post-dose measurement at given time point.

The POSNA-PODCI yields 4 functional assessment scores: Upper Extremity Function,Transfers and Basic Mobility, Sports and Physical Function, and Comfort/Pain. In addition, a Global Function score, which is an average of the 4 functional assessments, and a Happiness score are calculated. Raw, mean, standardized, and normative scores are calculated for each scale. Normative scores are calculated so that higher scores indicate better functioning. All scores are referenced to the general, healthy population with a normative mean score of 50 and a standard deviation of 10.

ITT Analysis Set: all participants who received at least 1 dose of study therapy and had at least 1 post-dose measurement at given time point.

The POSNA-PODCI yields 4 functional assessment scores: Upper Extremity Function,Transfers and Basic Mobility, Sports and Physical Function, and Comfort/Pain. In addition, a Global Function score, which is an average of the 4 functional assessments, and a Happiness score are calculated. Raw, mean, standardized, and normative scores are calculated for each scale. Normative scores are calculated so that higher scores indicate better functioning. All scores are referenced to the general, healthy population with a normative mean score of 50 and a standard deviation of 10.

ITT Analysis Set: all participants who received at least 1 dose of study therapy and had at least 1 post-dose measurement at given time point.

The POSNA-PODCI yields 4 functional assessment scores: Upper Extremity Function,Transfers and Basic Mobility, Sports and Physical Function, and Comfort/Pain. In addition, a Global Function score, which is an average of the 4 functional assessments, and a Happiness score are calculated. Raw, mean, standardized, and normative scores are calculated for each scale. Normative scores are calculated so that higher scores indicate better functioning. All scores are referenced to the general, healthy population with a normative mean score of 50 and a standard deviation of 10.

ITT Analysis Set: all participants who received at least 1 dose of study therapy and had at least 1 post-dose measurement at given time point.

The POSNA-PODCI yields 4 functional assessment scores: Upper Extremity Function,Transfers and Basic Mobility, Sports and Physical Function, and Comfort/Pain. In addition, a Global Function score, which is an average of the 4 functional assessments, and a Happiness score are calculated. Raw, mean, standardized, and normative scores are calculated for each scale. Normative scores are calculated so that higher scores indicate better functioning. All scores are referenced to the general, healthy population with a normative mean score of 50 and a standard deviation of 10.

ITT Analysis Set: all participants who received at least 1 dose of study therapy and had at least 1 post-dose measurement at given time point.

The POSNA-PODCI yields 4 functional assessment scores: Upper Extremity Function,Transfers and Basic Mobility, Sports and Physical Function, and Comfort/Pain. In addition, a Global Function score, which is an average of the 4 functional assessments, and a Happiness score are calculated. Raw, mean, standardized, and normative scores are calculated for each scale. Normative scores are calculated so that higher scores indicate better functioning. All scores are referenced to the general, healthy population with a normative mean score of 50 and a standard deviation of 10.

ITT Analysis Set: all participants who received at least 1 dose of study therapy and had at least 1 post-dose measurement at given time point.

FEP is defined as 100% × (urine phosphorus × serum creatinine)/(urine creatinine × serum phosphorus), where the 2-hour urine sample was used for urine phosphorus and urine creatinine.

Safety Analysis Set: All participants who received at least 1 dose of study therapy and had an assessment at given time point.

PK/PD Analysis Set: all participants who received at least 1 dose of therapy and had evaluable serum data at given time point.

PK/PD Analysis Set: all participants who received at least 1 dose of therapy and had evaluable serum data at given time point.

PK/PD Analysis Set: all participants who received at least 1 dose of therapy and had evaluable serum data at given time point.

PK/PD Analysis Set: all participants who received at least 1 dose of therapy and had evaluable serum data at given time point.

PK/PD Analysis Set: all participants who received at least 1 dose of therapy and had evaluable serum data at given time point.

An AE is defined as any untoward medical occurrence associated with the use of a drug in humans, whether or not considered drug related. An SAE is defined as an AE or suspected adverse reaction that at any dose results in any of the following outcomes: death; life-threatening AE; inpatient hospitalization or prolongation of existing hospitalization; persistent or significant incapacity or substantial disruption of the ability to conduct normal life functions; a congenital anomaly/birth defect. Severity was graded as 1 (mild), 2 (moderate), 3 (severe), 4 (life-threatening), 5 (death). TEAEs are defined as AEs with onset on or after the time of initiation of study drug administration.

Safety Analysis Set: All participants who received at least 1 dose of study therapy.