Extension Study to Evaluate the Long Term Safety and Efficacy of Denosumab in the Treatment of Osteoporosis

EXPERIMENTAL: Denosumab

Participants received a 60 mg subcutaneous injection of denosumab every 6 months for seven years.

Biological: Denosumab

Administered by subcutaneous injection once every 6 months.

Other Names:

• Prolia
• AMG 162

Number of Participants With Adverse Events (AEs)

A serious adverse event (SAE) is defined as an adverse event that: • is fatal • is life threatening • requires in-patient hospitalization or prolongation of existing hospitalization • results in persistent or significant disability/incapacity • is a congenital anomaly/birth defect • is other significant medical hazard. Treatment-related adverse events includes only events for which the investigator indicated there was a reasonable possibility they may have been caused by study drug. The following were classified as adverse events of interest (events that are considered to be identified or potential risks of denosumab treatment): positively adjudicated osteonecrosis of the jaw, positively adjudicated atypical femoral fracture, hypocalcemia, adverse events potentially related to hypersensitivity, serious infection (including bacterial cellulitis), malignancy, cardiac disorders, vascular disorders, fracture healing complications, eczema, acute pancreatitis, and musculoskeletal pain.

Number of Participants With Laboratory Toxicities of Grade ≥ 3

Laboratory toxicity grading was based on Common Terminology Criteria for Adverse Events (CTCAE) version 3.0. Grade 3 indicates severe toxicity and Grade 4 indicates life-threatening toxicity.

Number of Participants With Antibodies to Denosumab

Percent Change From Baseline in Lumbar Spine Bone Mineral Density by Visit

Lumbar spine bone mineral density (BMD) was measured by dual x-ray absorptiometry (DXA). DXA scans were analyzed by a central imaging center.

Percent Change From Baseline in Total Hip Bone Mineral Density by Visit

Total hip bone mineral density was measured by dual x-ray absorptiometry (DXA). DXA scans were analyzed by a central imaging center.

Percent Change From Baseline in Femoral Neck Bone Mineral Density by Visit

Femoral neck bone mineral density was measured by dual x-ray absorptiometry (DXA). DXA scans were analyzed by a central imaging center.

Percent Change From Baseline in 1/3 Radius Bone Mineral Density by Visit

1/3 radius bone mineral density was measured in a subset of participants by dual x-ray absorptiometry (DXA). DXA scans were analyzed by a central imaging center.

Percent Change From Study 20030216 Baseline in Lumbar Spine Bone Mineral Density by Visit

Lumbar spine bone mineral density was measured by dual x-ray absorptiometry (DXA). DXA scans were analyzed by a central imaging center. Measurements at some time points during the core study 20030216 were only taken in a subset of participants.

Percent Change From Study 20030216 Baseline in Total Hip BMD by Visit

Total hip bone mineral density was measured by dual x-ray absorptiometry (DXA). DXA scans were analyzed by a central imaging center. Measurements at some time points during the core study 20030216 were only taken in a subset of participants.

Percent Change From Study 20030216 Baseline in Femoral Neck BMD by Visit

Femoral neck bone mineral density was measured by dual x-ray absorptiometry (DXA). DXA scans were analyzed by a central imaging center. Measurements at some time points during the core study 20030216 were only taken in a subset of participants.

Percent Change From Study 20030216 Baseline in 1/3 Radius BMD by Visit

1/3 radius BMD was measured by dual x-ray absorptiometry (DXA). DXA scans were analyzed by a central imaging center. Measurements at some time points during the core study 20030216 were only taken in a subset of participants.

Number of Participants With New Vertebral Fractures

A new vertebral fracture, assessed by lateral spine X-ray using Genant semiquantitative scoring method, was identified as an ≥ 1 grade increase from the previous grade of 0 in any vertebra from T4 to L4, excluding any fracture associated with high trauma severity or a pathologic fracture.

Number of Participants With Non-Vertebral Fractures

Non-vertebral fractures (osteoporotic) were defined as a fracture present on a copy of radiographs or other diagnostic images such as computerized tomography (CT) or magnetic resonance imaging (MRI) confirming the fracture, and/or documented in a copy of the radiology report, surgical report, or discharge summary, excluding skull, facial, mandible, cervical vertebrae, thoracic vertebrae, lumbar vertebrae, metacarpus, finger phalanges, and toe phalanges. In addition, fractures associated with high trauma severity or pathologic fractures were excluded.

Percent Change From Baseline in C-Telopeptide 1 (CTX-1) by Visit

Bone turnover markers were collected in a subset of participants who participated in the 20030216 Bone Marker sub-study and in new participants continuing beyond month 24 who were not previously in the Bone Turnover Markers sub-study.

Percent Change From Baseline in Procollagen Type 1 N-telopeptide (P1NP) by Visit

Bone turnover markers were collected in a subset of participants who participated in the 20030216 Bone Marker sub-study and in new sparticipants continuing beyond month 24 who were not previously in the Bone Turnover Markers sub-study.

Percent Change From Study 20030216 Baseline in CTX-1 by Visit

Bone turnover markers were collected in a subset of participants who participated in the 20030216 Bone Marker sub-study and in new participants continuing beyond month 24 who were not previously in the Bone Turnover Markers sub-study.

Percent Change From Study 20030216 Baseline in P1NP by Visit

Bone turnover markers were collected in a subset of participants who participated in the 20030216 Bone Marker sub-study and in new participants continuing beyond month 24 who were not previously in the Bone Turnover Markers sub-study.

Percent Change From Baseline in Albumin-adjusted Serum Calcium at Day 10

Serum Denosumab Concentration

Serum concentrations of denosumab were measured by a validated conventional sandwich enzyme-linked immunosorbent assay (ELISA). The lower limit of quantification (LLOQ) was 0.8 ng/mL. Values of 0 in the table below indicate data below the lower limit of quantification.

Bone Histomorphometry: Cancellous Bone Volume

Bone biopsy samples were prepared according to standard procedures for bone histomorphometry. Cancellous (trabecular) bone volume is the percent of the total marrow cavity that is occupied by cancellous bone (both mineralized and non-mineralized) measured by quantitative histomorphometry.

Bone Histomorphometry: Trabecular Number

Bone biopsy samples were prepared according to standard procedures for bone histomorphometry. Trabecular number is the number of trabeculae present per lineal mm and is calculated as trabecular bone volume/trabecular thickness. Trabecular number is a measure of trabecular connectivity and decreases with bone loss.

Bone Histomorphometry: Trabecular Separation

Bone biopsy samples were prepared according to standard procedures for bone histomorphometry. Trabecular separation is the mean distance between trabeculae (measured by integrated computer graphics). Trabecular separation increases with trabecular bone loss.

Bone Histomorphometry: Trabecular Thickness

Bone biopsy samples were prepared according to standard procedures for bone histomorphometry. Mean trabecular thickness is a measure of trabecular structure and is calculated as the reciprocal of total bone (trabecular) surfaces. Trabecular thickness is reduced by aging and osteoporosis.

Bone Histomorphometry: Cortical Width

Bone biopsy samples were prepared according to standard procedures for bone histomorphometry. Cortical width is the average width of both inner and outer cortices.

Bone Histomorphometry: Cancellous Bone Volume by TRAP Histomorphometry

Bone biopsy samples were prepared according to standard procedures for bone histomorphometry. Cancellous (trabecular) bone volume is the percent of the total marrow cavity that is occupied by cancellous bone (both mineralized and non-mineralized) measured by tartrate-resistant acid phosphatase (TRAP) staining histomorphometry.

Bone Histomorphometry: Surface Density

Bone biopsy samples were prepared according to standard procedures for bone histomorphometry. Surface density is calculated by total bone (trabecular) surfaces / total tissue volume.

Bone Histomorphometry: Osteoblast - Osteoid Interface

Bone biopsy samples were prepared according to standard procedures for bone histomorphometry. Osteoblast - osteoid interface is calculated as osteoblast surface / osteoid surface * 100.

Bone Histomorphometry: Osteoid Surface

Bone biopsy samples were prepared according to standard procedures for bone histomorphometry. Osteoid surface is the percent of bone surface covered in osteoid.

Bone Histomorphometry: Osteoid Thickness

Bone biopsy samples were prepared according to standard procedures for bone histomorphometry. Osteoid thickness (width) is the mean thickness of osteoid seams on cancellous surfaces. Osteoid thickness is normally <12.5 µm. Increased osteoid thickness suggests abnormal mineralization (osteomalacia).

Bone Histomorphometry: Wall Thickness

Bone biopsy samples were prepared according to standard procedures for bone histomorphometry. Wall thickness is the average thickness of trabecular bone structural units (BSU) and is used to assess the overall balance between resorption and formation.

Bone Histomorphometry: Eroded Surface/Bone Surface

Bone biopsy samples were prepared according to standard procedures for bone histomorphometry.

Eroded surface/bone surface is the percentage of bone surface occupied by eroded (resorption) cavities (Howships lacunae), with or without osteoclasts.

Bone Histomorphometry: Osteoclast Number - Length Based

Bone biopsy samples were prepared according to standard procedures for bone histomorphometry.

Osteoclast number was measured by quantitative histomorphometry and is expressed per mm of bone.

Bone Histomorphometry: Osteoclast Number - Surface Based

Bone biopsy samples were prepared according to standard procedures for bone histomorphometry.

Osteoclast number was measured by quantitative histomorphometry and is expressed per 100 mm of bone surface area.

Bone Histomorphometry: Osteoclast Number by TRAP - Length Based

Bone biopsy samples were prepared according to standard procedures for bone histomorphometry.

Osteoclast number was measured using TRAP staining and is expressed per mm of bone.

Bone Histomorphometry: Osteoclast Number by TRAP - Surface Based

Bone biopsy samples were prepared according to standard procedures for bone histomorphometry.

Osteoclast number was measured using TRAP staining and is expressed per 100 mm of bone surface.

Da

Bone Histomorphometry: Single-label Surface

Bone biopsy samples were prepared according to standard procedures for bone histomorphometry.

A double tetracycline labeling procedure was used to allow visualization and quantification of sites of new bone formation. Tetracycline was given for two periods of 3 days separated by 14 days where no tetracycline was taken. A single label is deposited if formation either started or ended during the interval between the uses of the two courses of tetracycline administration. Single-label surface is expressed as a percentage of total bone surface.

Bone Histomorphometry: Double-label Surface

Bone biopsy samples were prepared according to standard procedures for bone histomorphometry.

A double tetracycline labeling procedure was used to allow visualization and quantification of sites of new bone formation. Tetracycline was given for two periods of 3 days separated by 14 days where no tetracycline was taken. The presence of double labels indicates that normal bone mineralization was actively occurring over the entire labeling interval. Double-label surface is expressed as a percentage of total bone surface.

Bone Histomorphometry: Mineralizing Surface

Bone biopsy samples were prepared according to standard procedures for bone histomorphometry.

A double tetracycline labeling procedure was used to allow visualization and quantification of sites of new bone formation. Tetracycline was given for two periods of 3 days separated by 14 days where no tetracycline was taken. Total mineralizing surfaces (MS) include all double and half of single-labeled surfaces. MS is expressed as a percentage of total bone surface.

Bone Histomorphometry: Mineral Apposition Rate

Bone biopsy samples were prepared according to standard procedures for bone histomorphometry.

A double tetracycline labeling procedure was used to allow visualization and quantification of sites of new bone formation. Tetracycline was given for two periods of 3 days separated by 14 days where no tetracycline was taken. The mineral apposition rate (MAR) is the avarage rate at which new bone mineral is being added on any actively forming surface. MAR is calculated as the average distance between visible labels, divided by the labeling interval.

Bone Histomorphometry: Adjusted Apposition Rate

Bone biopsy samples were prepared according to standard procedures for bone histomorphometry.

A double tetracycline labeling procedure was used to allow visualization and quantification of sites of new bone formation. Tetracycline was given for two periods of 3 days separated by 14 days where no tetracycline was taken. The mineral apposition rate (MAR) is the average rate at which new bone mineral is being added on any actively forming surface. Adjusted MAR is calculated as: (average distance between visible labels / labeling interval) * (total mineralizing surface/total bone surface).

Bone Histomorphometry: Bone Formation Rate - Surface Based

Bone biopsy samples were prepared according to standard procedures for bone histomorphometry.

A double tetracycline labeling procedure was used to allow visualization and quantification of sites of new bone formation. Tetracycline was given for two periods of 3 days separated by 14 days where no tetracycline was taken. Bone formation rate - surface based is the calculated rate at which cancellous bone surface is being replaced annually, derived from the Mineral Appositional Rate * 365 * (relative mineralizing surface / total bone surface).

Bone Histomorphometry: Bone Formation Rate - Volume Based

Bone biopsy samples were prepared according to standard procedures for bone histomorphometry.

A double tetracycline labeling procedure was used to allow visualization and quantification of sites of new bone formation. Tetracycline was given for two periods of 3 days separated by 14 days where no tetracycline was taken. Bone formation rate - volume based is the calculated rate at which cancellous bone volume is being replaced annually, derived from the Mineral Appositional Rate * 365 * (relative mineralizing surface / total bone volume).

Bone Histomorphometry: Formation Period

Bone biopsy samples were prepared according to standard procedures for bone histomorphometry.

A double tetracycline labeling procedure was used to allow visualization and quantification of sites of new bone formation. Tetracycline was given for two periods of 3 days separated by 14 days where no tetracycline was taken. Formation period (FP) is the mean time required to rebuild a new bone structural unit or osteon from the cement line back to the bone surface at a single location, and is given by wall width / adjusted apposition rate.

Bone Histomorphometry: Activation Frequency

Bone biopsy samples were prepared according to standard procedures for bone histomorphometry.

A double tetracycline labeling procedure was used to allow visualization and quantification of sites of new bone formation. Tetracycline was given for two periods of 3 days separated by 14 days where no tetracycline was taken. The average time that it takes for a new remodeling cycle to begin on any point on a cancellous surface is called the activation frequency. Activation frequency is calculated as the bone formation rate / wall width.

Bone Histomorphometry: Osteoid Volume

Bone biopsy samples were prepared according to standard procedures for bone histomorphometry.

Osteoid volume is the percentage of a given volume of bone tissue that consists of unmineralized bone (osteoid).

Bone Histomorphometry: Mineralization Lag Time

Bone biopsy samples were prepared according to standard procedures for bone histomorphometry. A double tetracycline labeling procedure was used to allow visualization and quantification of sites of new bone formation. Tetracycline was given for two periods of 3 days separated by 14 days where no tetracycline was taken.

Mineralization lag time is the average time interval between osteoid formation and its subsequent mineralization and is calculated by dividing the osteoid width by the apposition rate.

Bone Histology at Month 24

Bone biopsy samples were prepared according to standard procedures for bone histology to determine if there were any histological abnormalities in the bone. Results are reported for the number of biopsies with normal bone micro-architecture: normal lamellar bone, normal mineralization, and osteoid, and biopsies with abnormal bone histology: osteomalacia, marrow fibrosis, or woven bone.

Bone Histology at Month 84

Bone biopsy samples were prepared according to standard procedures for bone histology to determine if there were any histological abnormalities in the bone. Results are reported for the number of biopsies with normal bone micro-architecture: normal lamellar bone, normal mineralization, and osteoid, and biopsies with abnormal bone histology: osteomalacia, marrow fibrosis, or woven bone.