A Phase 2 Study of PTX 100 in Patients With Relapsed/Refractory CTCL

An Open-Label, Phase 2 Study of PTX-100 Monotherapy in Patients With Relapsed or Refractory Cutaneous T-Cell Lymphoma.

This is an open-label, phase 2 randomized study to evaluate the efficacy, safety, pharmacokinetics (PK) and pharmadynamics (PD), of PTX-100 monotherapy at 500 or 1000 mg/m2 in patients with relapsed/refractory Cutaneous T-Cell Lymphoma (CTCL).

PTX-100 will be administered by IV infusion over 60 minutes on days 1 to 5 of a 14-day cycle for 4 cycles, then 21 day cycle thereafter. Subjects will be treated or followed up, if subjects discontinue treatment, for up to 18 months.

Study Overview

• Status: Recruiting
• Conditions: CTCL
• Intervention / Treatment: Drug: PTX-100

Detailed Description

PTX-100 from a Phase I study shown to help some CTCL patients. This Phase II study will be conducted in a larger population size and there will be initially two groups/arms in the first phase called Phase 2a. This phase will randomize and enroll 20 subjects into the 500 mg/m2 and 20 subjects into the 1000 mg/m2 PTX treatment arms. After determining the recommended optimal dose from phase 2a, for Phase 2b, 75 subjects will then be allocated into this single arm part of the study.

Once subject has signed the informed consent, subject will undergo a 28 day screening period, where eligibility would be determined. Once subject is eligible, subject will be dosed with IP. Safety bloods will be taken on the first day of every cycle. Pharmacokinetics (PKs) which are blood samples sent to the Sponsors associated laboratory and will be analysed on how PTX-100 interacts biologically. PKs will be taken on Cycle1Day1(C1D1) to C1D5 and C1D8 for the first 4 cycles. Subject will also undergo skin evaluation and safety exams at every Cycle Day 1. Subjects will also complete quality of life questionnaires at every Cycle Day1. Subjects will be on the study for 18months, until disease progression, unacceptable toxicity, participant or Investigator decision, or until study treatment discontinuation criteria are met, whichever occurs first.

• Study Type: Interventional
• Enrollment (Estimated): 115
• Phase: Phase 2

Contacts and Locations

• Study Contact: Name: Upaly Bahadure; Phone Number: +61 3 9692 7222; Email: upaly@ptxtherapeutics.com
• Study Contact Backup: Name: David Wong; Email: david.wong@ptxtherapeutics.com

Study Locations

• Australia
  • New South Wales
    • Westmead, New South Wales, Australia, 2145
      • Recruiting
      • Westmead Hospital
      • Contact: Phone Number: 61 (02) 8890 5555
      • Principal Investigator: Ian Bilmon, MD
  • Victoria
    • Melbourne, Victoria, Australia, 3002
      • Recruiting
      • Epworth Healthcare
      • Principal Investigator: Miles Prince, MD
      • Contact: Ashna Saini; Phone Number: 61 (03)9483 6039; Email: Ashna.saini@epworth.org.au
  • Western Australia
    • Nedlands, Western Australia, Australia, 6009
      • Recruiting
      • Linear Clinical Research
      • Contact: Phone Number: 61 1300 546 327
      • Principal Investigator: Dejan Radeski, MD
• France
  • Bordeaux
    • Bordeaux, Bordeaux, France, 33000
      • Not yet recruiting
      • CHU de Bordeaux - Hôpital Saint André
      • Principal Investigator: Marie BEYLOT-BARRY, MD, PhD
      • Contact: Phone Number: +33 5 56 79 56 79
  • Pierre-Benite
    • Lyon, Pierre-Benite, France, 69310
      • Not yet recruiting
      • Hôpital Lyon Sud
      • Principal Investigator: Stephane Dalle, MD, PhD
      • Contact: Phone Number: +33 4 78 86 16
  • Île-de-France Region
    • Paris, Île-de-France Region, France, 75010
      • Not yet recruiting
      • Hopital Saint Louis
      • Contact: Phone Number: +33 1 42 49 49 49
      • Principal Investigator: Adele De Masson, MD
• Italy
  • Bologna
    • Bologna, Bologna, Italy, 40138
      • Recruiting
      • IRCCS Azienda Ospedaliero Universitaria di Bologna - Policlinico S. Orsola-Malpighi
      • Principal Investigator: Pier Luigi Zinzani, MD
      • Contact: Phone Number: +39 051 214 1111
  • Brescia
    • Brescia, Brescia, Italy, 25123
      • Recruiting
      • Universita degli Studi Di Brescia-Azienda Socio Sanitaria Territoriale degli Spedali Civili di Brescia
      • Principal Investigator: Alessandra Tucci, MD
      • Contact: Phone Number: +39 030 39951
  • Milano
    • Milan, Milano, Italy, 20132
      • Recruiting
      • Istituto di Ricovero e Cura a Carattere Scientifico (IRCCS) - Ospedale San Raffaele (HSR) (Istituto Scientifico Universitario San Raffaele)
      • Contact: Phone Number: +39 02 26431
      • Principal Investigator: Andres M J J. Ferreri, MD
• United States
  • California
    • Duarte, California, United States, 91010
      • Recruiting
      • City of Hope Comprehensive Cancer Cente
      • Principal Investigator: Christiane Querfeld, MD, PhD
      • Contact: Linda Devine; Phone Number: +1 800-826-4673
    • Irvine, California, United States, 92697
      • Recruiting
      • University of California Irvine
      • Contact: Phone Number: 714-456-7890
      • Principal Investigator: Lauren Pinter-Brown, MD
  • Connecticut
    • New Haven, Connecticut, United States, 06510
      • Recruiting
      • Yale Cancer Center
      • Contact: Phone Number: 203-785-4095
      • Principal Investigator: Francine M Foss, MD
  • Massachusetts
    • Boston, Massachusetts, United States, 022155450
      • Recruiting
      • Dana-Farber Cancer Institute
      • Principal Investigator: Eric Jacobsen, MD
      • Contact: Phone Number: +1 877-442-3324
  • New York
    • Rochester, New York, United States, 14642
      • Recruiting
      • Rochester Skin Lymphoma Medical Group. PLLC
      • Principal Investigator: Brian Poligone, MD, PhD
      • Contact: Brian Poligone, MD, PhD; Phone Number: 585-364-1188; Email: bpoligone@roclymphoma.com
  • Virginia
    • Richmond, Virginia, United States, 980037
      • Recruiting
      • Virginia Commonwealth University Massey Comprehensive Cancer Cente
      • Contact: Phone Number: 804-828-7999
      • Principal Investigator: Bruce Hough, MD

Participation Criteria

Eligibility Criteria

• Ages Eligible for Study: Adult; Older Adult
• Accepts Healthy Volunteers: No

Description

Inclusion Criteria:

1. Adult patient ≥18 years of age at the time of signing the informed consent.
2. Patient is capable of giving adequate signed informed consent
3. Have a confirmed diagnosis of CTCL with histological confirmation
4. Patients must have greater than or equal to Stage Ib disease.
5. Has received and failed (or intolerant of) at least 2 prior lines of prior systemic therapy for their disease.
6. Has measurable disease defined by at least one of the following, within 28 days prior to start of study treatment: by evaluable by mSWAT or quantifiable by flow cytometry or morphology in blood or measurable by Lugano Criteria.
7. On a stable dose of systemic corticosteroid (< 10 mg prednisone or equivalent) are permitted. Participants on a stable dose of topical corticosteroids are permitted.
8. Washout period- must be 2 weeks (4 weeks for monoclonal antibodies) or 5 -half-lives (whichever is longer) since any prior anti-cancer therapy.
9. Must be human T-cell lymphotropic virus type 1 (HTLV1) negative.
10. Has an ECOG PS of 0 to 2.
11. Life expectancy of 3 months or greater
12. Has adequate bone marrow function.
13. Has adequate hepatic function.
14. Has adequate Renal function.
15. Has adequate coagulation function.
16. Patients with Human Immunodeficiency virus (HIV) must be on established and stable effective anti-retroviral therapy for at least 4 weeks and have an HIV viral load of less than 400 copies/mL.
17. Male patients are eligible to participate if they agree to use a highly effective contraception during the treatment period and for at least 3 months after the last dose of study treatment and refrain from donating sperm during this period.

18. Female patients are eligible to participate if they are not pregnant, not breastfeeding, and at least one of the following conditions applies:

    -Not a woman of childbearing potential (WOCBP).

    • OR
    • A WOCBP who agrees to use a contraceptive method that is highly effective (with a failure rate of < 1% per year) or be abstinent from heterosexual intercourse as their preferred method and usual lifestyle, beginning the time of informed consent, during the treatment period and for at least 3 months after the last dose of study treatment.
19. A WOCBP must have a negative serum pregnancy within 72 hours of the first dose of study treatment.
20. Must be willing and able to adhere to the study as judged by the Investigator.

Exclusion Criteria:

1. Patients with known central nervous system involvement.
2. Patients who require the use of strong inhibitors or inducers of CYP enzymes or transporters (e.g., CYP3A4, 2D6, 2C19) or (P-gp, BCRP, OATP1B1, OATP1B3, OAT1. OAT3, OCT2, MATE1 and MATE2-K). Patients who are receiving these medications at Screening can be enrolled into the trial if they discontinue them for at least 14 days or 5 half-lives, whichever is longer, before they commence PTX-100. An alternative pharmacological treatment should be instituted by the treating clinician based on clinical judgement.
3. Significant cardiovascular disease. A history of, or concurrent interstitial lung disease or severely impaired lung function.

5. Active viral, bacterial, fungal infection or other serious infection requiring ongoing systemic treatment. Routine antimicrobial prophylaxis is permitted.

6. Medical history of another malignant tumor within the past 5 years. Exceptions are patients with basal cell carcinoma of the skin, squamous cell carcinoma of the skin or carcinoma in situ who have undergone curative therapy with no evidence of disease.

7. On an immunomodulatory drug for concomitant or intercurrent conditions or who have received any of these agents within 4 weeks of baseline.

8. Patients with active viral (any etiology) hepatitis are excluded. However, patients with serologic evidence of chronic hepatitis B virus (HBV) infection (defined by a positive hepatitis B surface antigen test and a positive anti-hepatitis core antigen antibody test) who have a viral load below the limit quantification (HBV deoxyribose nucleic acid titer < 1000 cps/mL or 200 IU/mL) and are not currently on viral suppressive therapy may be eligible and should be discussed with the Medical Monitor. Patients with a history of hepatitis C virus infection who have completed curative antiviral treatment and have a viral load below the limit of quantification may be eligible and should be discussed with the Medical Monitor.

9. A history or current evidence of any condition, laboratory abnormality or other circumstance that might confound the results of the study or interfere with patient participation for the full duration of the study.

10. Prior allogeneic or autologous hematopoietic transplantation 11. Has a known psychiatric disorder that would interfere with compliance with the requirements of the study.

12. Is a consumer of illicit or recreational drugs or has a recent history (within the last year) of drug or alcohol abuse or dependence that in the judgment of the Investigator, would interfere with compliance with the requirements of the study.

Study Plan

How is the study designed?

Design Details

• Primary Purpose: Treatment
• Allocation: Randomized
• Interventional Model: Parallel Assignment
• Masking: None (Open Label)

Number of Arms

3

Arms and Interventions

Participant Group / Arm	Intervention / Treatment
Experimental: Phase 2a PTX-100 500mg/m2; Phase 2a PTX-100 will be 500mg/m2 IV infusion over 60 minutes on days 1 to 5 of a 14-day cycle for 4 cycles. This is then followed by IV infusion over 60 minutes on days 1 to 5 of a 21-day cycle for up to 18months.	Drug: PTX-100; Peptidomimetic inhibitor of GGTase 1
Experimental: Phase 2a PTX-100 1000mg/m2; Phase 2a PTX-100 will be 1000mg/m2 IV infusion over 60 minutes on days 1 to 5 of a 14-day cycle for 4 cycles. This is then followed by IV infusion over 60 minutes on days 1 to 5 of a 21-day cycle for up to 18months.	Drug: PTX-100; Peptidomimetic inhibitor of GGTase 1
Experimental: Phase 2b PTX-100 Recommended Optimal Dose (ROD).; Phase 2b PTX-100 will be the Recommended Optimal Dose form Phase 2a and follow the same infusion timeline outlined previously. IV infusion of RD over 60 minutes on days 1 to 5 of a 14-day cycle for 4 cycles then followed by IV infusion of RD over 60 minutes on days 1 to 5 of a 21-day cycle up to 18months.	Drug: PTX-100; Peptidomimetic inhibitor of GGTase 1

What is the study measuring?

Primary Outcome Measures

Outcome Measure	Measure Description	Time Frame
To determine the efficacy of PTX-100 as determined by ORR.	Objective response rate (ORR): ORR is defined as the proportion of patients who achieved CR or PR as their best response	18 months from day of first treatment until disease progression, unacceptable toxicity, participant or Investigator decision.

Secondary Outcome Measures

Outcome Measure	Measure Description	Time Frame
To further characterize the efficacy of PTX-100	Skin response as per Modified Severity-Weighted Assessment Tool (mSWAT). The mSWAT uses body surface area in 12 body areas to calculate involvement. A weighting factor is also used: Patches, which are flat, earned a multiplier of one. Plaques, which are raised, earned a multiplier of two. Tumors, which are larger and solid, earned a multiplier of three. Lesion BSA multiplied with the weighting factor with the sum of regions affected gives a final mSWAT score. The SWAT result is a number is monitored over time. A stable number suggested a stable condition. A lower number suggested less active CTCL and conversely, a higher number suggested more active CTCL.	Within 18 months after PTX-100 initial dose.
Progression-free survival (PFS)	Defined as the time from the date of PTX-100 initiation to the date of first documented progression or death.	Within 18 months after PTX-100 initial dose.
Time to response (TTR)	TTR: defined as the time from the date of PTX-100 initiation to first confirmed objective response (CR or PR)	Within 18 months after PTX-100 initial dose.
Overall survival (OS)	OS: defined as the time interval between the date of PTX-100 initiation and the date of death due to any cause	Within 18 months after PTX-100 initial dose.
Duration of response (DoR)	DoR: defined as the time interval between the first confirmed objective response (CR or PR) and the first occurrence of objective progression (PD) or death from any cause.	Within 18 months after PTX-100 initial dose.
Complete response rate (CRR)	Complete response rate (CRR) evaluated according to the Lugano2014 criteria.	Within 18 months after PTX-100 initial dose.
Pharmacokinetics (PK) of PTX-100: Cmax	PTX-100 peak plasma concentration (Cmax) in plasma	Cycle 1: Day 1 and Day 5: pre-dose, 5 mins post-infusion, and at 1, 2, 4, 6, and 8 hours after dose. Day 2, 3 and 4: 24 hours after previous dose, bloods taken at Pre and at 5 mins post-infusion. Day 8; 72 hours after the Day 5 dose and prior to dosing.
Pharmacokinetics (PK) of PTX-100: Tmax	Time to peak drug concentration in plasma (Tmax)	Cycle 1: Day 1 and Day 5: pre-dose, 5 mins post-infusion, and at 1, 2, 4, 6, and 8 hours after dose. Day 2, 3 and 4: 24 hours after previous dose, bloods taken at Pre and at 5 mins post-infusion. Day 8; 72 hours after the Day 5 dose and prior to dosing.
Pharmacokinetics (PK) of PTX-100: Cmin	Cmin for the minimum blood plasma concentration reached by PTX-100 during the time interval between administration of two doses	Cycle 1: Day 1 and Day 5: pre-dose, 5 mins post-infusion, and at 1, 2, 4, 6, and 8 hours after dose. Day 2, 3 and 4: 24 hours after previous dose, bloods taken at Pre and at 5 mins post-infusion. Day 8; 72 hours after the Day 5 dose and prior to dosing.
Pharmacokinetics (PK) of PTX-100: AUCtau	AUCtau, area under the curve from time 0 to time tau (the dosing interval) at steady state. AUCtau is typically expressed in units of concentration multiplied by time (e.g., ng·h/mL)	Cycle 1: Day 1 and Day 5: pre-dose, 5 mins post-infusion, and at 1, 2, 4, 6, and 8 hours after dose. Day 2, 3 and 4: 24 hours after previous dose, bloods taken at Pre and at 5 mins post-infusion. Day 8; 72 hours after the Day 5 dose and prior to dosing.

Other Outcome Measures

Outcome Measure	Measure Description	Time Frame
To evaluate the effects of Health-related Quality of Life (QoL)	To collect the health related questionnaire for CTCL whihc includes Functional Assessment of Cancer Therapy -General (FACT-G), Skindex-29, European Quality of Life 5 Dimensions 3 Level Version (EQ-5D-3L) and ItchyQoL	From Baseline till end of study
Exploratory Biomarkers	Assessing Biomarker downstream signature of PTX-100 treatment: measurement value (and the change from baseline and throughout the study) of gene/ protein expression in blood samples for each subject using Olink Explore HT high-throughput platform	From Baseline till end of study

Collaborators and Investigators

• Sponsor: Prescient Therapeutics, Ltd.

Study record dates

Study Major Dates

• Study Start (Actual): March 28, 2025
• Primary Completion (Estimated): January 1, 2028
• Study Completion (Estimated): June 1, 2028

Study Registration Dates

• First Submitted: February 18, 2025
• First Submitted That Met QC Criteria: February 25, 2025
• First Posted (Actual): March 3, 2025

Study Record Updates

• Last Update Posted (Actual): April 29, 2026
• Last Update Submitted That Met QC Criteria: April 28, 2026
• Last Verified: January 1, 2026

More Information

Terms related to this study

• Keywords: Non-Hodgkin Lymphoma; CTCL; Mycosis Fungoides; T Cell Lymphoma; Sezary Syndrome; Cutaneous Lymphoma; Relapsed or refractory Cutaneous T Cell Lymphoma; PTX-100
• Additional Relevant MeSH Terms: Pathologic Processes; Neoplasms; Disease Attributes; Immune System Diseases; Neoplasms by Histologic Type; Lymphatic Diseases; Lymphoproliferative Disorders; Immunoproliferative Disorders; Lymphoma; Pathological Conditions, Signs and Symptoms; Hemic and Lymphatic Diseases; Recurrence; Lymphoma, Non-Hodgkin; Lymphoma, T-Cell; Lymphoma, T-Cell, Cutaneous; Mycosis Fungoides; Sezary Syndrome
• Other Study ID Numbers: PTX-100-02-2024

Plan for Individual participant data (IPD)

• Plan to Share Individual Participant Data (IPD)?: NO

Drug and device information, study documents

• Studies a U.S. FDA-regulated drug product: Yes
• Studies a U.S. FDA-regulated device product: No
• product manufactured in and exported from the U.S.: No