Titre officiel
A Phase 1 Study of Metronomic Selinexor in Select Soft Tissue Sarcomas and Split Dosing of Selinexor in All Soft Tissue Sarcomas
Sommaire:
Il s’agit d’une étude de phase 1,
ouverte et monocentrique du médicament expérimental selinexor chez des
participants atteints de sarcomes des tissus mous qui ne peuvent être traités
par les thérapies standard. Le Selinexor a été administré à
3111 participants atteints de cancer à ce jour, dont 142 patients
atteints de sarcomes. Les premiers résultats ont montré que le selinexor est
efficace contre plusieurs types de cancer. L’étude actuelle vise à tester de
faibles doses et différents schémas posologiques de selinexor afin de vérifier
s’il réduit les effets secondaires sans compromettre les avantages. Cette étude
comporte 2 groupes : le groupe A et le groupe B. Groupe A (groupe d’augmentation
de la dose) : Les participants recevront du Selinexor par voie orale
4 jours par semaine afin de vérifier l’innocuité, la tolérance et l’effet
antitumoral de faibles doses de Selinexor chez les participants atteints de
tumeurs malignes de la gaine du nerf périphérique (TMGNP) avancées ou métastatiques,
de sarcomes stromaux endométriaux (SSE) et de léiomyosarcomes (LMS). Les
participants poursuivront l’étude jusqu’à la progression de la maladie ou l’apparition
d’effets secondaires inacceptables. Jusqu’à 36 participants seront
recrutés dans ce groupe. Groupe B : les participants présentant tout
sous-type de sarcome des tissus mous seront recrutés dans ce groupe. Ils
recevront des doses plates de Selinexor par voie orale une fois par semaine,
3 fois par jour. L’innocuité et la tolérance seront évaluées dans ce
groupe. Jusqu’à 20 participants seront recrutés et ils continueront à
recevoir du selinexor jusqu’à la progression de la maladie ou l’apparition d’effets
secondaires inacceptables. Le cancer est la croissance incontrôlée de cellules
humaines. L’un des moyens par lesquels les cellules cancéreuses continuent à se
développer consiste à se débarrasser de protéines appelées « protéines
suppresseuses de tumeurs » qui, normalement, provoqueraient la mort des
cellules cancéreuses. Le médicament étudié agit en piégeant les « protéines
suppresseuses de tumeurs » à l’intérieur de la cellule, ce qui entraîne la mort
ou l’arrêt de la croissance des cellules cancéreuses. L’étude comprend
3 périodes : le dépistage (jusqu’à 28 jours), le médicament à l’étude
(jusqu’à la progression de la maladie) et le suivi de la survie (une fois tous
les 3 mois). Les procédures à des fins de recherche uniquement
comprendront une prise de sang et un questionnaire d’étude.
Description de l'essai
Primary Outcome:
- Incidence of toxicity and safety of Selinexor given on either a metronomic (Arm A) or split dosing (Arm B) schedule: Adverse Events
- Recommended phase 2 dose of Selinexor given metronomically
Secondary Outcome:
- Progression-Free Survival (PFS) of metronomic Selinexor
- Objective Response Rate (ORR) of metronomic Selinexor
- Clinical Benefit Rate (CBR) of metronomic Selinexor
- Peak Plasma Concentration (Cmax) of metronomic Selinexor
- Area under the plasma concentration versus time curve (AUC) of metronomic Selinexor
- Characterization of the toxicity of metronomic Selinexor
- Quality of life assessment using Quality of Life Questionnaire
Background:
Soft tissue sarcomas (STS):
STS are a group of heterogeneous mesenchymal derived tumours with many histological types that
account for approximately 1% of adult tumours and 15% of pediatric tumours. STS can be divided
into those with simple genetic alterations (e.g. translocations or activating mutations) or
karyotypic complex lesions. However, most subclasses are treated in the same manner. Surgery
is the primary treatment for localized STS, with or without radiation therapy (RT), but
approximately 10% of patients will present with metastatic disease.
For patients who present with metastatic disease, or those with locally advanced/unresectable
or have failed primary therapy, cytotoxic chemotherapy is usually the treatment of choice
which may provide meaningful palliation or prolong survival. Traditionally, doxorubicin
containing regimens, in combination with ifosfamide or as a single agent are standard first
line therapies. Combination based doxorubicin containing regimens have shown higher response
rates and progression free survival at the expense of more toxicity when compared to
doxorubicin alone. However, no combination regimen has been associated with increased overall
survival compared to doxorubicin alone.
In the metastatic setting, STS carry a poor prognosis related to a lack of chemo-sensitivity
and a lack of systemic therapeutic options. Exportin 1 (XPO1 or chromosome region maintenance
1 [CRM1]) is the sole nuclear exporter of some tumour suppressor proteins (TSP). XPO1 is
over-expressed 2-4 fold in a variety of solid and hematological tumours with higher levels
correlating with poorer outcomes.
Selinexor:
Selinexor is a novel, oral, small-molecule XPO1 inhibitor which forces reactivation of TSPs
and thus leads to apoptosis of tumour cells. Preclinical data of Selinexor has shown promising
in-vitro tumour regression in sarcoma. In two phase I studies, single agent clinical activity
in the form of prolonged stable disease was seen in STS. Twice weekly dosing aided
tolerability with a MTD declared at 65mg/m2 for solid tumours and 60mg flat dosing was the
RP2D based on better tolerability given problems related to gastrointestinal toxicity however
these doses were still difficult for patients to take due to the toxicity profile. A Phase 1b
study has been performed combining Selinexor once weekly oral dosing with doxorubicin given
at the standard 3 weekly dose in advanced soft tissue sarcoma.
Previous studies have provided a signal of increased likelihood of benefit to particular
subtypes including metastatic malignant peripheral nerve sheath tumours (MPNST) and
endometrial stromal sarcomas (ESS). In the early phase studies, objective responses or
prolonged stable disease were demonstrated (n=3 for both MPNST and ESS). In this study, the
investigator also plans to include leiomyosarcoma (LMS) - such strategy will allow not only
seamless recruitment, but also generate treatment efficacy data for other rare types of
sarcomas.
Additionally, preclinical data has shown efficacy in using metronomic dosing of Selinexor.
The investigator hypothesizes that low dose Selinexor will improve tolerability of the drug
without impacting the clinical benefit that has been seen in other studies for patients with
particular histological subtypes of STS.
Rationale:
Biological Rationale:
More than 2500 patients with advanced cancers have received Selinexor orally in Phase 1 and
Phase 2-3 studies as of 31 May 2019. Based on the preclinical and clinical findings to date,
Selinexor dosing is limited to ≤70 mg/m2 (≤120 mg) maximum dose in adults. The plan going
forward is that Selinexor will be administered primarily as fixed milligram doses, as
analyses of Phase 1 pharmacokinetic (PK) data indicated that exposure is not strongly
correlated with Body Surface Area (BSA).
An interim analysis of preliminary results was performed to determine the RP2D for future
studies. The results of this analysis suggest that, overall, Selinexor doses > 65 mg do not
appear to provide additional efficacy responses beyond those seen with the 60 mg dose
(described herein as 45-65 mg dose level, median 60 mg) with the exception of activity in
refractory multiple myeloma (MM), where the RP2D is Selinexor 80 mg in combination with 20mg
dexamethasone. Importantly, response results with Selinexor 45-65 mg twice weekly were
comparable for both hematologic malignancies (excluding MM) and solid tumours.
The currently available selinexor formulation (20 mg tablet) and dosage is quite toxic
particularly in terms of gastrointestinal disturbance, particularly nausea and vomiting. As a
result of these difficulties it might be beneficial to investigate alternate formulations of
selinexor or a different dosing schedule of the currently available selinexor formulation. A
PK study in male Beagle dogs has been completed by Karyopharm investigating a new extended
release (ER) formulation of Selinexor 20 mg tablets showing favourable results.
Dose Schedule Rationale:
In the present study, Selinexor will be given using two different schedules according to
Schema for Arm A (metronomic) and Schema for Arm B (split dosing).
In Arm A Selinexor will be administered at a fixed oral dose as per dose level (starting at
2.5mg PO 4 days on, 3 days off repeated weekly) of each 4-week (28-day) cycle a total of 16
doses per cycle. The maximum dose for Selinexor in this study will be 17.5mg PO flat dosing 4
days on, 3 days off, weekly. This arm of the study will be aimed at identifying the RP2D and
toxicity profile of this new selinexor dosing schedule.
In Arm B patients will be treated with Selinexor 40mg in the morning, 20mg in the afternoon
and 20mg at night on days 1, 8, 15 and 22 of a 28-day cycle. The hope is that this alternate
dosing schedule will improve the tolerability of this formulation of selinexor without
impacting its clinical benefit.
Intervention and mode of delivery:
In Arm A patients will receive Selinexor orally as described above. The initial 3 patients
will be enrolled to the first Selinexor dose level of 2.5mg (DL1). Three patients will be
assessed per cohort for at least 1 cycle and dose escalation or de-escalation rules will
follow 3+3 dosing. The first dose of study treatment for the first two patients will be
staggered by 7 days. Intra-patient dose escalation is not permitted at any time during the
treatment plan.
In Arm B also patients will receive selinexor orally as described above.
Duration of Intervention and Evaluation:
Treatment in both arms with Selinexor will be repeated on a 28-day cycle until radiographic
or symptomatic progression on imaging or the development of unacceptable toxicity. Patients
will be restaged every 2 cycles until unacceptable toxicity or disease progression.
Subsequent follow-up for disease progression will continue by telephone or review of patient
medical records for up to 2 years after the completion of trial treatment.
Number of Patients:
A total of up to 36 patients will be accrued in Arm A. Up to 20 patients will be enrolled in
Arm B with an anticipated accrual period of 12 to 18 months.
Definition of dose limiting toxicity (DLT):
DLT is defined as any of the following occurring in the first 28 days of each dose level that
is considered at least possibly related to drug administration:
≥ 4 missed doses (out of 16) due to a toxicity that is at least possibly study drug related.
Discontinuation of a patient due a toxicity that is at least possibly study drug related
before completing cycle 1
Non-Hematologic:
Grade ≥ 3 nausea/vomiting, dehydration or diarrhea while taking optimal supportive
medications Grade 3 fatigue lasting for ≥ 7 days while taking optimal supportive care and
with correction of dehydration, anorexia, anemia, endocrine, or electrolyte abnormalities.
Grade 3 AST or ALT elevation lasting longer than 7 days OR Grade 3 AST or ALT elevation in
the setting of bilirubin elevation > 2x ULN (> 2X baseline for patients with Gilbert's
syndrome) OR any grade 4 AST or ALT elevation.
Any other clinically significant Grade ≥ 3 non-hematological toxicity except alopecia or
electrolyte abnormalities correctable with supportive therapy Any cardiac disorder ≥ CTCAE
Grade 3
Hematologic:
Grade 4 neutropenia [absolute neutrophil count (ANC) < 0.5x109/L] on Cycle 2 Day 1 that does
not resolve to G1 within 7 days Grade 4 neutropenia [absolute neutrophil count (ANC) <
0.5x109/L] within the first 28 days lasting ≥ 7 days Grade 3 Febrile neutropenia Grade ≥ 3
thrombocytopenia associated with clinically significant bleeding Grade 4 thrombocytopenia
within the first 28 days (platelets < 25x109/L) lasting > 7days
Other:
Any hematologic or non-hematologic toxicity that results in the inability to administer day 1
of the next planned cycle within 14 days of the planned end of the previous cycle.
Treatment related death During the dose escalation portion of the study, patients who missed
>1 dose of Selinexor during Cycle 1 for reasons unrelated to study drug are not evaluable for
DLT and will be replaced.
Treatment Discontinuation Criteria:
Disease progression Noncompliance with protocol Need for treatment with medications not
allowed by the study protocol Consent withdrawal Intercurrent illness Incidence or severity
of AEs Investigator discretion
Duration:
The treatment period for an individual patient is expected to be approximately between 2 and
12 months, however there is no maximum treatment duration.
Study procedures:
For Arm A the starting dose of Selinexor will be 2.5mg given 4 days on 3 days off on a weekly
basis as part of a 28-day cycle. For Arm B patients will receive oral Selinexor 40 mg in the
morning, 20 mg in the afternoon, 20 mg in the evening. Patients will be assessed for response
after ever 2 cycles. Treatment will be given until disease progression or unacceptable
toxicity.
Safety data:
Overall safety profile as per NCI CTCAE version 5.
Concomitant Medications:
Patients will receive best supportive care, including anti-emetics, appetite stimulants and
growth factors, blood product transfusions, antimicrobials and (as appropriate) granulocyte
colony-stimulating factors (G-CSF) for neutropenia and/or neutropenic infection,
erythropoietin for anemia, and/or platelet-stimulating factors for thrombocytopenia. Patients
will not be dosed with G-CSF in the first cycle for primary prophylaxis of febrile
neutropenia.
If clinically indicated and as required by protocol, patients may receive red blood cell or
platelet transfusions, acetaminophen, serotonin (5-HT3) receptor subtype antagonists (e.g.,
ondansetron) megestrol acetate, and olanzapine in addition to ondansetron. Patients
intolerant to 5-HT3 antagonists may receive D2-antagonists instead. Additional anti-nausea
and anti-anorexia agents may be given as needed. Patients may continue to receive baseline
medication(s), and may receive concomitant medications that are medically necessary as
standard care to treat co-morbid diseases, AEs, and intercurrent illnesses.
Concurrent therapy with any other approved or investigative anticancer therapy is not
allowed.
Pharmacokinetic and Pharmacodynamic assessments:
PK will be determined at various times following administration of Selinexor in Arm A.
Pharmacokinetics:
In the metronomic arm for the first 3 patients in each dose level, blood samples just before
Selinexor administration (C1D1), and at 1hr, 2hr, 4hr, 24hr and a trough level pre C2 will be
collected.
Response:
Objective disease response assessment will be made according to standard, international
RECIST 1.1 criteria for solid tumours.
Safety Variables and Analysis:
The safety and tolerability of Selinexor will be evaluated by means of drug related DLT, AE
reports, physical examinations, and clinically significant laboratory safety evaluations. NCI
CTCAE version 5.0 will be used for grading of AEs.
Investigators will provide their assessment of causality as: unrelated, possibly related, or
probably or definitely related for all AEs.
Voir cet essai sur ClinicalTrials.gov
