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ARRx in Combination With Enzalutamide in Metastatic Castration Resistant Prostate Cancer

ARRO-CITO: (UMCC 2017.055) Phase Ib/II Single-Arm Multi-Center Study of IONIS-AR-2.5Rx, a Next Generation Androgen Receptor Antisense Oligonucleotide, in Combination With Enzalutamide in Metastatic Castration Resistant Prostate Cancer

Status
Terminated
Phases
Phase 1
Study type
Interventional
Source
ClinicalTrials.gov
Registry ID
NCT03300505
Enrollment
9
Registered
2017-10-03
Start date
2019-05-31
Completion date
2023-01-24
Last updated
2025-05-13

For informational purposes only — not medical advice. Sourced from public registries and may not reflect the latest updates. Terms

Conditions

Prostate Cancer

Brief summary

The purpose of this study is to test the effectiveness (how well the drug works), safety, and tolerability of the investigational drug combination of ARRx (also known as AZD5312) plus enzalutamide in patients with metastatic castration resistant prostate cancer.

Detailed description

This is a single dose-finding one-arm phase Ib/II trial to determine the maximum tolerated dose (MTD) from among three dose levels of ARRx in combination with a fixed dose of enzalutamide and to obtain a preliminary estimate of efficacy at this MTD, as measured by PSA response rate. Success for the trial is defined as finding a dose level that is likely to be both tolerable and effective. The study was originally registered as a phase 1/ phase 2 study; however, the study was cancelled by the sponsor before opening the phase 2 portion. Outcome measures were updated to include those relevant to the Phase 1 portion as the study was terminated before enrolling into phase 2

Interventions

DRUGARRx

Given intravenously (IV)

DRUGEnzalutamide

Given by mouth (PO)

Sponsors

National Cancer Institute (NCI)
CollaboratorNIH
University of Michigan Rogel Cancer Center
Lead SponsorOTHER

Study design

Allocation
NA
Intervention model
SINGLE_GROUP
Primary purpose
TREATMENT
Masking
NONE

Eligibility

Sex/Gender
MALE
Age
18 Years to No maximum
Healthy volunteers
No

Inclusion criteria

* Ability to understand and voluntarily agree to participate by providing written informed consent for the trial. * Histologically confirmed prostate adenocarcinoma cancer, either pure or mixed. Small cell/neuroendocrine differentiation is not allowed. * Castrate levels of serum testosterone (≤ 50 ng/dL). Patients must continue androgen deprivation therapy with an LHRH analogue or antagonist if they have not undergone bilateral orchiectomy. * Patients must have metastatic disease; either non-measurable disease OR measurable disease per RECIST 1.1. * Progressive disease despite ongoing treatment with Androgen Deprivation Therapy (ADT). * Patients treated with first generation anti-androgen as most recent systemic therapy (e.g. bicalutamide, nilutamide) must have at least 4 weeks elapsed from treatment discontinuation to start of protocol therapy with evidence of disease progression (per protocol) following discontinuation of prior anti-androgen. * Minimum PSA at entry of 1 ng/mL is required. * ECOG Performance Status 0, 1 or 2. * Be ≥18 years of age on the day of signing informed consent. * Demonstrate adequate organ function. * Subjects must agree to use an adequate method of contraception as outlined in the protocol starting with the time of informed consent through 120 days after the last dose trial therapy.

Exclusion criteria

* Prior chemotherapy and/or enzalutamide for metastatic castration-resistant prostate cancer. Chemotherapy administered in the castration-sensitive setting is allowed provided last dose of chemotherapy was greater than 6 months prior to study entry. * Is currently participating and receiving study therapy or has participated in a study of an investigational agent and received study therapy or used an investigation device within 4 weeks prior to enrollment. * Has not recovered (i.e., AE ≤Grade 1 or at baseline) from AEs due to a previously administered agent. Subjects with ≤Grade 2 neuropathy or ≤Grade 2 alopecia are an exception to this criterion and are allowed if relevant toxicity is stabilized. * If subjects received major surgery they must have recovered adequately from the toxicity and/or complications from the intervention prior to starting trial therapy. * Has a known additional malignancy that is progressing or requires active treatment. Exceptions include basal cell carcinoma of the skin or squamous cell carcinoma of the skin. * Has known psychiatric or substance abuse disorders that would interfere with cooperation with the requirements of the trial. At the time of signing informed consent is a known regular user (including recreational use) of any illicit drug(s) or had a recent history (within the last year) of drug or alcohol abuse. * Has a known history of human immunodeficiency virus (HIV) (HIV 1/2 antibodies). * Has known active hepatitis B (e.g., HBsAg reactive) or hepatitis C (e.g., HCV RNA \[qualitative\] is detected). * Has received a live virus vaccine within 30 days of planned start of trial therapy. * Has known active CNS metastases and/or carcinomatous meningitis. Subjects with previously treated brain metastases may participate provided they have stable brain metastases (stability is normally defined as a period of 1 to 3 months in which there is no evidence of new or enlarging CNS metastases). * Has symptomatic ascites or pleural effusion; a subject who is clinically stable following treatment for these conditions is eligible. * Has had a prior allogeneic stem cell or bone marrow transplant. * Has known contraindication to aspirin (81 mg).

Design outcomes

Primary

MeasureTime frameDescription
Number of Subjects With Dose-limiting Toxicity (DLT) During the First Cycle of ARRx (in Combination With Enzalutamide)Up to day 21 of treatmentDLTs will be counted based on the number of subjects with DLT at a given dose level. No single subject can trigger more than one DLT event. DLT is defined as any Grade 3 or higher toxicity as defined by CTCAE v5.0. Toxicity that is clearly and directly related to the primary disease or to another etiology is excluded from this definition.
Best PSA Response3.5 yearsNumber of subjects with at least 50% decline in PSA from Baseline

Secondary

MeasureTime frameDescription
Percentage of Patients With a Reduction in PSA of at Least 30% From Baseline3.5 yearsUsing PCWG3 criteria. Number of patient with a reduction in PSA of at least 30% from baseline
Overall Survival at One Year1 yearOne year KM estimate. Patients alive or lost to follow-up at the time of analysis will be censored at their last date of follow-up.
Intrapatient Dose Delays3.5 yearsNumber of participants that experienced dose delays while on study treatment
Intrapatient Dose Reductions3.5 yearsNumber of participants that experienced dose reductions while on study treatment

Countries

United States

Participant flow

Participants by arm

ArmCount
Dose Level 1
Phase 1b: All registered subjects will be treated with ARRx (ASO) in combination with enzalutamide. ARRx will be given intravenously on Days 1, 4, 8, 11, 15 on cycle 1, then on days 1, 8, 15 in subsequent 21-day cycles. Enzalutamide will be taken daily in 21 day cycles starting Day 1 of cycle 1. Treatment will continue until clinical or radiologic progression or unacceptable toxicity. ARRx: Given intravenously (IV) Enzalutamide: Given by mouth (PO) Dose Level 1: 600 mg IONIS Dose Level 2: 750 mg IONIS Dose Level 3: 900 mg IONIS
1
Dose Level 2
Phase 1b: All registered subjects will be treated with ARRx (ASO) in combination with enzalutamide. ARRx will be given intravenously on Days 1, 4, 8, 11, 15 on cycle 1, then on days 1, 8, 15 in subsequent 21-day cycles. Enzalutamide will be taken daily in 21 day cycles starting Day 1 of cycle 1. Treatment will continue until clinical or radiologic progression or unacceptable toxicity. ARRx: Given intravenously (IV) Enzalutamide: Given by mouth (PO) Dose Level 1: 600 mg IONIS Dose Level 2: 750 mg IONIS Dose Level 3: 900 mg IONIS
5
Dose Level 3
Phase 1b: All registered subjects will be treated with ARRx (ASO) in combination with enzalutamide. ARRx will be given intravenously on Days 1, 4, 8, 11, 15 on cycle 1, then on days 1, 8, 15 in subsequent 21-day cycles. Enzalutamide will be taken daily in 21 day cycles starting Day 1 of cycle 1. Treatment will continue until clinical or radiologic progression or unacceptable toxicity. ARRx: Given intravenously (IV) Enzalutamide: Given by mouth (PO) Dose Level 1: 600 mg IONIS Dose Level 2: 750 mg IONIS Dose Level 3: 900 mg IONIS
3
Total9

Withdrawals & dropouts

PeriodReasonFG000FG001FG002
Overall StudyAdverse Event002
Overall StudyDeath010
Overall StudySponsor Termination010
Overall StudyWithdrawal by Subject011

Baseline characteristics

CharacteristicDose Level 1Dose Level 2Dose Level 3Total
Age, Categorical
<=18 years
0 Participants0 Participants0 Participants0 Participants
Age, Categorical
>=65 years
0 Participants4 Participants2 Participants6 Participants
Age, Categorical
Between 18 and 65 years
0 Participants1 Participants1 Participants2 Participants
Ethnicity (NIH/OMB)
Hispanic or Latino
0 Participants0 Participants0 Participants0 Participants
Ethnicity (NIH/OMB)
Not Hispanic or Latino
0 Participants5 Participants3 Participants8 Participants
Ethnicity (NIH/OMB)
Unknown or Not Reported
0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
American Indian or Alaska Native
0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
Asian
0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
Black or African American
0 Participants1 Participants1 Participants2 Participants
Race (NIH/OMB)
More than one race
0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
Native Hawaiian or Other Pacific Islander
0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
Unknown or Not Reported
0 Participants0 Participants0 Participants0 Participants
Race (NIH/OMB)
White
0 Participants4 Participants2 Participants6 Participants
Region of Enrollment
United States
5 participants3 participants8 participants
Sex: Female, Male
Female
0 Participants0 Participants0 Participants0 Participants
Sex: Female, Male
Male
0 Participants5 Participants3 Participants8 Participants

Adverse events

Event typeEG000
affected / at risk
EG001
affected / at risk
EG002
affected / at risk
deaths
Total, all-cause mortality
0 / 01 / 50 / 3
other
Total, other adverse events
0 / 05 / 53 / 3
serious
Total, serious adverse events
0 / 12 / 51 / 3

Outcome results

Primary

Best PSA Response

Number of subjects with at least 50% decline in PSA from Baseline

Time frame: 3.5 years

Population: Only a single participant was included in the Dose Level 1 arm and data are not reported publicly to protect participant confidentiality

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Level 2Best PSA Response4 Participants
Level 3Best PSA Response3 Participants
Primary

Number of Subjects With Dose-limiting Toxicity (DLT) During the First Cycle of ARRx (in Combination With Enzalutamide)

DLTs will be counted based on the number of subjects with DLT at a given dose level. No single subject can trigger more than one DLT event. DLT is defined as any Grade 3 or higher toxicity as defined by CTCAE v5.0. Toxicity that is clearly and directly related to the primary disease or to another etiology is excluded from this definition.

Time frame: Up to day 21 of treatment

Population: Only a single participant was included in the Dose Level 1 arm and data are not reported publicly to protect participant confidentiality

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Level 2Number of Subjects With Dose-limiting Toxicity (DLT) During the First Cycle of ARRx (in Combination With Enzalutamide)0 Participants
Level 3Number of Subjects With Dose-limiting Toxicity (DLT) During the First Cycle of ARRx (in Combination With Enzalutamide)0 Participants
Secondary

Intrapatient Dose Delays

Number of participants that experienced dose delays while on study treatment

Time frame: 3.5 years

Population: Only a single participant was included in the Dose Level 1 arm and data are not reported publicly to protect participant confidentiality

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Level 2Intrapatient Dose Delays3 Participants
Level 3Intrapatient Dose Delays3 Participants
Secondary

Intrapatient Dose Reductions

Number of participants that experienced dose reductions while on study treatment

Time frame: 3.5 years

Population: Only a single participant was included in the Dose Level 1 arm and data are not reported publicly to protect participant confidentiality

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Level 2Intrapatient Dose Reductions1 Participants
Level 3Intrapatient Dose Reductions1 Participants
Secondary

Overall Survival at One Year

One year KM estimate. Patients alive or lost to follow-up at the time of analysis will be censored at their last date of follow-up.

Time frame: 1 year

Population: Only a single participant was included in the Dose Level 1 arm and data are not reported publicly to protect participant confidentiality

ArmMeasureValue (NUMBER)
Level 2Overall Survival at One Year67 percentage of participants
Level 3Overall Survival at One Year100 percentage of participants
Secondary

Percentage of Patients With a Reduction in PSA of at Least 30% From Baseline

Using PCWG3 criteria. Number of patient with a reduction in PSA of at least 30% from baseline

Time frame: 3.5 years

Population: Only a single participant was included in the Dose Level 1 arm and data are not reported publicly to protect participant confidentiality

ArmMeasureValue (COUNT_OF_PARTICIPANTS)
Level 2Percentage of Patients With a Reduction in PSA of at Least 30% From Baseline4 Participants
Level 3Percentage of Patients With a Reduction in PSA of at Least 30% From Baseline3 Participants

Source: ClinicalTrials.gov · Data processed: Feb 4, 2026