Clinical Pharmacology for Kisqali FeMara Co-Pack
Mechanism Of Action
Ribociclib is an inhibitor of cyclin-dependent kinase (CDK) 4 and 6. These kinases are activated upon binding to Dcyclins and play a crucial role in signaling pathways, which lead to cell cycle progression and cellular proliferation. The cyclin D-CDK4/6 complex regulates cell cycle progression through phosphorylation of the retinoblastoma protein (pRb).
In vitro, ribociclib decreased pRb phosphorylation leading to arrest in the G1 phase of the cell cycle and reduced cell proliferation in breast cancer cell lines. In vivo, treatment with single agent ribociclib in a rat xenograft model with human tumor cells led to decreased tumor volumes, which correlated with inhibition of pRb phosphorylation.
Letrozole is a nonsteroidal competitive inhibitor of the aromatase enzyme system by competitively binding to the heme of the cytochrome P450 subunit of the enzyme, resulting in a reduction of estrogen biosynthesis in all tissues. In postmenopausal women, estrogens are mainly derived from the action of the aromatase enzyme, which converts adrenal androgens (primarily androstenedione and testosterone) to estrone and estradiol. The suppression of estrogen biosynthesis in peripheral tissues and in the cancer tissue itself can therefore be achieved by specifically inhibiting the aromatase enzyme.
In vivo studies, using patient-derived estrogen receptor positive breast cancer xenograft models, combination of ribociclib and antiestrogen (e.g., letrozole) resulted in increased tumor growth inhibition compared to each drug alone.
Pharmacodynamics
Ribociclib
Cardiac Electrophysiology
Serial, triplicate ECGs were collected following a single dose and at steady-state to evaluate the effect of ribociclib on the QTcF interval in patients with advanced cancer. A pharmacokinetic-pharmacodynamic analysis included a total of 997 patients treated with ribociclib at doses ranging from 50 to 1200 mg. The analysis suggested that ribociclib causes concentration-dependent increases in the QTcF interval. The estimated mean change from baseline in QTcF for KISQALI 600 mg in combination with aromatase inhibitors was 22.0 ms (90% CI: 22.0, 23.4) at the geometric mean Cmax at steadystate [see WARNINGS AND PRECAUTIONS].
Letrozole
In postmenopausal patients with advanced breast cancer, daily doses of 0.1 mg to 5 mg FEMARA (letrozole) suppress plasma concentrations of estradiol, estrone, and estrone sulfate by 75% to 95% from baseline with maximal suppression achieved within two-three days. Suppression is dose-related, with doses of 0.5 mg and higher giving many values of estrone and estrone sulfate that were below the limit of detection in the assays. Estrogen suppression was maintained throughout treatment in all patients treated at 0.5 mg or higher.
Letrozole is highly specific in inhibiting aromatase activity. There is no impairment of adrenal steroidogenesis. No clinically relevant changes were found in the plasma concentrations of cortisol, aldosterone, 11-deoxycortisol, 17- hydroxy-progesterone, adrenocorticotropic hormone (ACTH) or in plasma renin activity among postmenopausal patients treated with a daily dose of FEMARA 0.1 mg to 5 mg. The ACTH stimulation test performed after 6 and 12 weeks of treatment with daily doses of 0.1, 0.25, 0.5, 1, 2.5, and 5 mg did not indicate any attenuation of aldosterone or cortisol production. Glucocorticoid or mineralocorticoid supplementation is, therefore, not necessary.
No changes were noted in plasma concentrations of androgens (androstenedione and testosterone) among healthy postmenopausal women after 0.1, 0.5, and 2.5 mg single doses of FEMARA or in plasma concentrations of androstenedione among postmenopausal patients treated with daily doses of 0.1 mg to 5 mg. This indicates that the blockade of estrogen biosynthesis does not lead to accumulation of androgenic precursors. Plasma levels of luteinizing hormone (LH) and follicle-stimulating hormone (FSH) were not affected by letrozole in patients, nor was thyroid function as evaluated by thyroid stimulating hormone (TSH) levels, T3 uptake, and T4 levels.
Pharmacokinetics
Ribociclib exhibited over-proportional increases in exposure (peak plasma concentrations (Cmax) and area under the time concentration curve (AUC)) across the dose range of 50 mg to 1200 mg following both single dose and repeated doses. Following repeated 600 mg once daily administration, steady-state was generally achieved after 8 days and ribociclib accumulated with a geometric mean accumulation ratio of 2.51 (range, 0.972 to 6.40).
Letrozole’s terminal elimination half-life is about 2 days and steady-state plasma concentration after daily 2.5 mg dosing is reached in 2-6 weeks. Plasma concentrations at steady state are 1.5 to 2 times higher than predicted from the concentrations measured after a single dose, indicating a slight non-linearity in the pharmacokinetics of letrozole upon daily administration of 2.5 mg. These steady-state levels are maintained over extended periods, however, and continuous accumulation of letrozole does not occur.
Absorption And Distribution
Ribociclib
The time to reach Cmax (Tmax) following ribociclib administration was between 1 and 4 hours. The mean absolute bioavailability of ribociclib after a single oral dose of 600 mg was 65.8%.
Binding of ribociclib to human plasma proteins in vitro was approximately 70% and independent of concentration (10 to 10,000 ng/mL). Ribociclib was equally distributed between red blood cells and plasma with a mean in vivo blood-toplasma ratio of 1.04. The apparent volume of distribution at steady-state (Vss/F) was 1090 L based on population PK analysis.
Food Effect
Compared to the fasted state, oral administration of a single 600 mg dose of KISQALI film-coated tablet with a high-fat, high-calorie meal (approximately 800 to 1000 calories with ~50% calories from fat, ~35% calories from carbohydrates, and ~15% calories from protein) had no effect on the rate and extent of absorption of ribociclib (Cmax GMR: 1.00; 90% CI: 0.898, 1.11; AUCinf GMR: 1.06; 90% CI: 1.01, 1.12).
Letrozole
Letrozole is rapidly and completely absorbed from the gastrointestinal tract and absorption is not affected by food. It is metabolized slowly to an inactive metabolite whose glucuronide conjugate is excreted renally, representing the major clearance pathway. About 90% of radiolabeled letrozole is recovered in urine.
Letrozole is weakly protein bound and has a large volume of distribution (approximately 1.9 L/kg).
Metabolism And Elimination/Excretion
Ribociclib
In vitro and in vivo studies indicated ribociclib undergoes extensive hepatic metabolism mainly via CYP3A4 in humans.
Following oral administration of a single 600 mg dose of radiolabeled ribociclib to humans, the primary metabolic pathways for ribociclib involved oxidation (dealkylation, C and/or N-oxygenation, oxidation (-2H)) and combinations thereof. Phase II conjugates of ribociclib Phase I metabolites involved N-acetylation, sulfation, cysteine conjugation, glycosylation, and glucuronidation. Ribociclib was the major circulating drug-derived entity in plasma (44%). The major circulating metabolites included metabolite M13 (CCI284, N-hydroxylation), M4 (LEQ803, N-demethylation), and M1 (secondary glucuronide), each representing an estimated 9%, 9%, and 8% of total radioactivity, and 22%, 20%, and 18% of ribociclib exposure. Clinical activity (pharmacological and safety) of ribociclib was due primarily to parent drug, with negligible contribution from circulating metabolites.
Ribociclib was extensively metabolized with unchanged drug accounting for 17% and 12% in feces and urine, respectively. Metabolite LEQ803 was a significant metabolite in excreta and represented approximately 14% and 4% of the administered dose in feces and urine, respectively. Numerous other metabolites were detected in both feces and urine in minor amounts (≤ 3% of the administered dose).
The geometric mean plasma effective half-life (based on accumulation ratio) was 32.0 hours (63% CV) and the geometric mean apparent oral clearance (CL/F) was 25.5 L/hr (66% CV) at steady-state at 600 mg in patients with advanced cancer. The geometric mean apparent plasma terminal half-life (T½) of ribociclib ranged from 29.7 to 54.7 hours and geometric mean CL/F of ribociclib ranged from 39.9 to 77.5 L/hr at 600 mg across studies in healthy subjects.
Ribociclib is eliminated mainly via feces, with a small contribution of the renal route. In 6 healthy male subjects, following a single oral dose of radiolabeled ribociclib, 92% of the total administered radioactive dose was recovered within 22 days; feces was the major route of excretion (69%), with 23% of the dose recovered in urine.
Letrozole
Metabolism to a pharmacologically-inactive carbinol metabolite (4,4'methanol-bisbenzonitrile) and renal excretion of the glucuronide conjugate of this metabolite is the major pathway of letrozole clearance. Of the radiolabel recovered in urine, at least 75% was the glucuronide of the carbinol metabolite, about 9% was two unidentified metabolites, and 6% was unchanged letrozole.
In human microsomes with specific CYP isozyme activity, CYP3A4 metabolized letrozole to the carbinol metabolite while CYP2A6 formed both this metabolite and its ketone analog. In human liver microsomes, letrozole inhibited CYP2A6 and inhibited CYP2C19, however, the clinical significance of these findings is unknown.
Specific Populations
Patients With Hepatic Impairment
Ribociclib
Based on a pharmacokinetic trial in patients with hepatic impairment, mild (Child-Pugh class A) hepatic impairment had no effect on the exposure of ribociclib. The mean exposure for ribociclib was increased less than 2-fold in patients with moderate (Child-Pugh class B; geometric mean ratio [GMR]: 1.44 for Cmax; 1.28 for AUCinf) or severe (Child-Pugh class C; GMR: 1.32 for Cmax; 1.29 for AUCinf) hepatic impairment. Based on a population pharmacokinetic analysis that included 160 patients with normal hepatic function and 47 patients with mild hepatic impairment, mild hepatic impairment had no effect on the exposure of ribociclib, further supporting the findings from the dedicated hepatic impairment study.
Letrozole
The effect of hepatic impairment on FEMARA exposure in noncirrhotic cancer patients with elevated bilirubin levels has not been determined.
In a study of subjects with mild to moderate non-metastatic hepatic dysfunction (e.g., cirrhosis, Child-Pugh class A and B), the mean AUC values of the volunteers with moderate hepatic impairment were 37% higher than in normal subjects, but still within the range seen in subjects without impaired function.
In a pharmacokinetic study, subjects with liver cirrhosis and severe hepatic impairment (Child-Pugh class C, which included bilirubins about 2-11 times ULN with minimal to severe ascites) had 2-fold increase in exposure (AUC) and 47% reduction in systemic clearance. Breast cancer patients with severe hepatic impairment are thus expected to be exposed to higher levels of letrozole than patients with normal liver function receiving similar doses of this drug [see Pharmacokinetics].
Patients With Renal Impairment
Ribociclib
The effect of renal impairment on the pharmacokinetics of ribociclib was assessed in a renal impairment study in noncancer subjects with normal renal function (eGFR ≥ 90 mL/min/1.73 m2, n = 9), severe renal impairment (eGFR 15 to < 30 mL/min/1.73 m2, n = 6), and End Stage Renal Disease (ESRD) (eGFR < 15 mL/min/1.73 m2, n = 4) at a single ribociclib dose of 400 mg/day. In subjects with severe renal impairment and ESRD, AUCinf increased 2.37-fold and 3.81- fold, and Cmax increased 2.10-fold and 2.68-fold relative to the exposure in non-cancer study participants with normal renal function.
Mild (60 mL/min/1.73 m2 ≤ eGFR < 90 mL/min/1.73 m2) or moderate (30 mL/min/1.73 m2 ≤ eGFR < 60 mL/min/1.73 m2) renal impairment had no effect on the exposure of ribociclib based on a population PK analysis that included 438 cancer patients with normal renal function, 488 patients with mild renal impairment and 113 patients with moderate renal impairment. In addition, in a sub-group analysis of data from studies following oral administration of ribociclib 600 mg as a single dose or repeat doses in cancer patients with mild or moderate renal impairment, AUC and Cmax were comparable to patients with normal renal function, suggesting no clinically meaningful effect of mild or moderate renal impairment on ribociclib exposure.
Letrozole
In a study of volunteers with varying renal function (24-hour creatinine clearance: 9 to 116 mL/min), no effect of renal function on the pharmacokinetics of single doses of 2.5 mg of FEMARA was found. In addition, in a study of 347 patients with advanced breast cancer, about half of whom received 2.5 mg FEMARA and half 0.5 mg FEMARA, renal impairment (calculated creatinine clearance: 20 to 50 mL/min) did not affect steady-state plasma letrozole concentrations.
Additional Pharmacokinetic Information on Ribociclib
The pharmacokinetics of ribociclib was investigated in patients with advanced cancer following oral daily doses ranging from 50 mg to 1200 mg. Healthy subjects received single oral doses of 400 or 600 mg or repeated daily oral doses (8 days) at 400 mg.
Effect Of Age, Weight, Gender, And Race
Population PK analysis showed that there are no clinically relevant effects of age, body weight, gender, or race on the systemic exposure of ribociclib.
Drug Interaction Studies
Drugs That Affect Ribociclib Plasma Concentrations
CYP3A Inhibitors
A drug interaction trial in healthy subjects was conducted with ritonavir (a strong CYP3A inhibitor).
Compared to ribociclib alone, ritonavir (100 mg twice a day for 14 days) increased ribociclib Cmax and AUCinf by 1.7-fold and 3.2-fold, respectively, following a single 400 mg ribociclib dose. Cmax and AUC for LEQ803 (a prominent metabolite of LEE011, accounting for less than 10% of parent exposure) decreased by 96% and 98%, respectively. A moderate CYP3A4 inhibitor (erythromycin) is predicted to increase ribociclib Cmax and AUC by 1.3-fold and 1.9-fold, respectively.
CYP3A Inducers
A drug interaction trial in healthy subjects was conducted with rifampicin (a strong CYP3A4 inducer). Compared to ribociclib alone, rifampicin (600 mg daily for 14 days) decreased ribociclib Cmax and AUCinf by 81% and 89%, respectively, following a single 600 mg ribociclib dose. LEQ803 Cmax increased 1.7-fold and AUCinf decreased by 27%, respectively. A moderate CYP3A inducer (efavirenz) is predicted to decrease ribociclib Cmax and AUC by 37% and 60%, respectively.
Drugs That Are Affected By KISQALI
CYP3A4 and CYP1A2 Substrates
A drug interaction trial in healthy subjects was conducted as a cocktail study with midazolam (sensitive CYP3A4 substrate) and caffeine (sensitive CYP1A2 substrate). Compared to midazolam and caffeine alone, multiple doses of ribociclib (400 mg once daily for 8 days) increased midazolam Cmax and AUCinf by 2.1- fold and 3.8-fold, respectively. Administration of ribociclib at 600 mg once daily is predicted to increase midazolam Cmax and AUC by 2.4-fold and 5.2-fold, respectively. The effect of multiple doses of 400 mg ribociclib on caffeine was minimal, with Cmax decreased by 10% and AUCinf increased slightly by 20%. Only weak inhibitory effects on CYP1A2 substrates are predicted at 600 mg ribociclib once daily dose.
Gastric pH-Elevating Agents
Coadministration of ribociclib with drugs that elevate the gastric pH was not evaluated in a clinical trial; however, altered ribociclib absorption was not identified in a population PK analysis and was not predicted using physiology based PK models.
Letrozole
Data from a clinical trial in patients with breast cancer and population PK analysis indicated no drug interaction between ribociclib and letrozole following coadministration of the drugs.
Anastrozole
Data from a clinical trial in patients with breast cancer indicated no clinically relevant drug interaction between ribociclib and anastrozole following coadministration of the drugs.
Exemestan
Data from a clinical trial in patients with breast cancer indicated no clinically relevant drug interaction between ribociclib and exemestane following coadministration of the drugs.
Fulvestrant
Data from a clinical trial in patients with breast cancer indicated no clinically relevant effect of fulvestrant on ribociclib exposure following coadministration of the drugs.
Tamoxifen
KISQALI is not indicated for concomitant use with tamoxifen. Data from a clinical trial in patients with breast cancer indicated that tamoxifen Cmax and AUC increased approximately 2-fold following coadministration of 600 mg ribociclib.
In Vitro Studies
Effect of Ribociclib on CYP Enzymes
In vitro, ribociclib was a reversible inhibitor of CYP1A2, CYP2E1, and CYP3A4/5 and a time-dependent inhibitor of CYP3A4/5, at clinically relevant concentrations. In vitro evaluations indicated that KISQALI has no potential to inhibit the activities of CYP2A6, CYP2B6, CYP2C8, CYP2C9, CYP2C19, and CYP2D6 at clinically relevant concentrations. It has no potential for time-dependent inhibition of CYP1A2, CYP2C9, and CYP2D6, and no induction of CYP1A2, CYP2B6, CYP2C9, and CYP3A4 at clinically relevant concentrations.
Effect of Ribociclib on Transporters
In vitro evaluations indicated that KISQALI has a low potential to inhibit the activities of drug transporters P-gp, OATP1B1/B3, OCT1, MATEK2 at clinically relevant concentrations. KISQALI may inhibit BCRP, OCT2, MATE1, and human BSEP at clinically relevant concentrations.
Effect of Transporters on Ribociclib
Based on in vitro data, P-gp, and BCRP mediated transport are unlikely to affect the extent of oral absorption of ribociclib at therapeutic doses. Ribociclib is not a substrate for hepatic uptake transporters OATP1B1/1B3 or OCT-1 in vitro.
Animal Toxicology And/Or Pharmacology
Ribociclib
In vivo cardiac safety studies in dogs demonstrated dose and concentration related QTc interval prolongation at an exposure similar to patients receiving the recommended dose of 600 mg. There is a potential to induce incidences of premature ventricular contractions (PVCs) at elevated exposures (approximately 5-fold the anticipated clinical Cmax).
Clinical Studies
MONALEESA-2: KISQALI In Combination With Letrozole
Postmenopausal Women with HR-positive, HER2-negative Advanced or Metastatic Breast Cancer for Initial Endocrine- Based Therapy
MONALEESA-2 (NCT01958021) was a randomized, double-blind, placebo-controlled, multicenter clinical study of KISQALI plus letrozole vs. placebo plus letrozole conducted in postmenopausal women with HR-positive, HER2- negative, advanced breast cancer who received no prior therapy for advanced disease.
A total of 668 patients were randomized to receive either KISQALI and letrozole (n = 334) or placebo and letrozole (n = 334), stratified according to the presence of liver and/or lung metastases. Letrozole 2.5 mg was given orally once daily for 28 days, with either KISQALI 600 mg or placebo orally once daily for 21 consecutive days followed by 7 days off until disease progression or unacceptable toxicity. The major efficacy outcome measure for the study was investigator-assessed progression-free survival (PFS) using Response Evaluation Criteria in Solid Tumors (RECIST v1.1).
Patients enrolled in MONALEESA-2 had a median age of 62 years (range, 23 to 91) and 45% of patients were older than 65. The majority of patients were White (82%), and all patients had an ECOG performance status of 0 or 1. A total of 47% of patients had received chemotherapy and 51% had received anti-hormonal therapy in the neoadjuvant or adjuvant setting. Thirty-four percent (34%) of patients had de novo metastatic disease, 21% had bone-only disease, and 59% had visceral disease.
The efficacy results from MONALEESA-2 are summarized in Table 12, Figure 1, and Figure 2. The PFS assessment based on a blinded independent central radiological review was consistent with investigator assessment.
Consistent results were observed across patient subgroups of prior adjuvant or neoadjuvant chemotherapy or hormonal therapies, liver and/or lung involvement, and bone-only metastatic disease.
Table 12: Efficacy Results – MONALEESA-2 (Investigator Assessment, Intent-to-Treat Population)
|
KISQALI + Letrozole |
Placebo + Letrozole |
| Progression-Free Survival |
N = 334 |
N = 334 |
| Events (%) |
93 (27.8) |
150 (44.9) |
| Median (months, 95% CI) |
NR (19.3 – NR) |
14.7 (13.0 – 16.5) |
| Hazard ratio (95% CI) |
0.556 (0.429, 0.720) |
| p-valuea |
< 0.0001a |
| Overall survival |
N = 334 |
N = 334 |
| Events (%) |
181 (54.2%) |
219 (65.6%) |
| Median (months, 95% CI) |
63.9 (52.4, 71.0) |
51.4 (47.2, 59.7) |
| Hazard ratio (95% CI) |
0.765 (0.628, 0.932) |
| p-value |
0.004a |
| Overall response rate |
N = 256 |
N = 245 |
| Patients with measurable disease (95% CI) |
52.7 (46.6, 58.9) |
37.1 (31.1, 43.2) |
Abbreviations: CI, confidence interval; NR, not reached.
a p-value estimated from one-sided log-rank test. |
Figure 1 Kaplan-Meier Progression-Free Survival Curves – MONALEESA-2 (Intent-to-Treat Population)
Figure 2 Kaplan-Meier plot of Overall Survival Curves – MONALEESA-2 (Intent-to-Treat Population)
MONALEESA-7: KISQALI In Combination With An Aromatase Inhibitor
Pre/perimenopausal Patients with HR-positive, HER2-negative Advanced or Metastatic Breast Cancer for Initial Endocrine-Based Therapy
MONALEESA-7 (NCT02278120) was a randomized, double-blind, placebo-controlled study of KISQALI plus either non-steroidal aromatase inhibitor (NSAI) or tamoxifen and goserelin vs. placebo plus either a NSAI or tamoxifen and goserelin conducted in pre/perimenopausal women with HR-positive, HER2-negative, advanced breast cancer who received no prior endocrine therapy for advanced disease.
A total of 672 patients were randomized to receive KISQALI plus NSAI or tamoxifen plus goserelin (n = 335) or placebo plus NSAI or tamoxifen plus goserelin (n = 337), stratified according to the presence of liver and/or lung metastases, prior chemotherapy for advanced disease, and endocrine combination partner (tamoxifen and goserelin vs. NSAI and goserelin). Among 248 patients who received KISQALI plus NSAI plus goserelin, 211 (85%) received letrozole and 37 (15%) received anastrozole.
NSAI (letrozole 2.5 mg or anastrozole 1 mg) or tamoxifen 20 mg were given orally once daily on a continuous daily schedule, goserelin was administered as a sub-cutaneous injection on Day 1 of each 28-day cycle, with either KISQALI 600 mg or placebo orally once daily for 21 consecutive days followed by 7 days off until disease progression or unacceptable toxicity. The major efficacy outcome measure for the study was investigator-assessed progression-free survival (PFS) using Response Evaluation Criteria in Solid Tumors (RECIST) v1.1.
Patients enrolled in MONALEESA-7 had a median age of 44 years (range, 25 to 58) and were primarily White (58%), Asian (29%), or Black (3%). Nearly all patients (99%) had an ECOG performance status of 0 or 1. Of the 672 patients, 33% had received chemotherapy in the adjuvant vs. 18% in the neoadjuvant setting and 40% had received endocrine therapy in the adjuvant vs. 0.7% in the neoadjuvant setting prior to study entry. Forty percent (40%) of patients had de novo metastatic disease, 24% had bone-only disease, and 57% had visceral disease. Demographics and baseline disease characteristics were balanced and comparable between study arms, and endocrine combination partner.
The efficacy results from a pre-specified subgroup analysis of 495 patients who had received KISQALI or placebo with NSAI plus goserelin are summarized in Table 13, Figure 3, and Figure 4. Consistent results were observed in the stratification factor subgroups of disease site and prior chemotherapy for advanced disease.
Table 13: Efficacy Results – MONALEESA-7 (NSAI)
|
KISQALI + NSAI + Goserelin |
Placebo + NSAI + Goserelin |
| Progression-free survival1 |
N = 248 |
N = 247 |
| Events (n, %) |
92 (37.1%) |
132 (53.4%) |
| Median (months, 95% CI) |
27.5 (19.1, NR) |
13.8 (12.6, 17.4) |
| Hazard ratio (95% CI) |
0.569 (0.436, 0.743) |
| Overall survival |
N = 248 |
N = 247 |
| Events (n, %) |
61 (24.6%) |
80 (32.4%) |
| Median (months, 95% CI) |
NR (NR, NR) |
40.7 (37.4, NR) |
| Hazard ratio (95% CI) |
0.699 (0.501, 0.976) |
| Overall response rate*,1 |
N = 192 |
N = 199 |
| Patients with measurable disease (95% CI) |
50.5 (43.4, 57.6) |
36.2 (29.5, 42.9) |
Abbreviations: CI, confidence interval; NR, not reached; NSAI, non-steroidal aromatase inhibitors.
*Based on confirmed responses.
1 Investigator Assessment. |
Figure 3 Kaplan-Meier Progression Free Survival Curves – MONALEESA-7 (NSAI, Investigator Assessment)
Figure 4 Kaplan-Meier Overall Survival Curves- MONALEESA-7 (NSAI)
COMPLEEMENT-1: KISQALI In Combination With Letrozole And Goserelin Or Leuprolide
Men with HR-positive, HER2-negative Advanced or Metastatic Breast Cancer for Initial Endocrine-Based Therapy
COMPLEEMENT-1 (NCT 02941926) was an open-label, multicenter clinical study of ribociclib in combination with letrozole and goserelin or leuprolide for the treatment of adults with HR-positive, HER2-negative, advanced breast cancer who received no prior hormonal therapy for advanced disease.
The study included 39 male patients who received KISQALI 600 mg orally once daily for 21 consecutive days followed by 7 days off; and letrozole 2.5 mg orally once daily for 28 days; and goserelin 3.6 mg as injectable subcutaneous implant or leuprolide 7.5 mg as intramuscular injection administered on Day 1 of each 28-day cycle. Patients were treated until disease progression or unacceptable toxicity occurred.
Male patients enrolled in this study had a median age of 62 years (range, 33 to 80). Of these patients, 39% were 65 years and older, including 10% aged 75 years and older. The male patients enrolled were White (72%), Asian (8%), and Black (3%), with 17% unknown. Nearly all male patients (97%) had an ECOG performance status of 0 or 1. The majority of male patients (97%) had 4 or less metastatic sites, which were primarily bone and visceral (69% each). Table 17 summarizes the efficacy results in male patients from COMPLEEMENT-1.
Table 14: Efficacy Results in Male Patients1 – COMPLEEMENT-1 (Investigator Assessment, Intent-to-Treat
|
KISQALI + Letrozole + Goserelin or Leuprolide |
| Overall Response Rate*,2 |
N = 32 |
| (95% CI) |
46.9 (29.1, 65.3) |
| Duration of Response (DoR)3 |
N = 15 |
| Median (months, 95% CI) |
NR (21.3, NR) |
| Patients with DoR ≥ 12 months, n (%) |
12 (80.0%) |
Abbreviations: CI, confidence interval, NR, not reached.
*Based on confirmed responses.
1 Patients with measurable disease.
2 Investigator Assessment.
3 Patients with complete response or partial response. |