GT Biopharma Provides Enrollment Update on GTB-3650 Phase 1 Trial in Patients with Relapsed or Refractory (r/r) CD33 Expressing Hematologic Malignancies
GT Biopharma (NASDAQ: GTBP) reported that the formal safety review of Cohort 3 (5 µg/kg/day) in the Phase 1 GTB-3650 trial completed with no safety or tolerability issues, enabling advancement to Cohort 4 (10 µg/kg/day). Six patients have been treated across Cohorts 1–3. Cohort 4 dosing is expected to begin in the coming weeks and is considered more reflective of a potential efficacy threshold based on positive trends in multiple immunologic biomarkers and absence of dose-limiting toxicities. The protocol allows escalation to Cohorts 5–7 (25, 50, 100 µg/kg/day) if needed. The trial plans up to ~14 patients and will assess safety, PK/PD, NK cell expansion, and clinical activity. Next update expected Q1 2026.
GT Biopharma (NASDAQ: GTBP) ha comunicato che la revisione formale di sicurezza della Coorte 3 (5 µg/kg/giorno) nello studio di fase 1 GTB-3650 si è chiusa senza problemi di sicurezza o tollerabilità, permettendo l'avanzamento alla Coorte 4 (10 µg/kg/giorno). Sei pazienti sono stati trattati nei Corsi 1–3. L'inizio della somministrazione della Coorte 4 è previsto nelle prossime settimane e si ritiene che rifletta meglio un possibile umbral di efficacia, basato su tendenze positive in molteplici biomarcatori immunologici e sull'assenza di tossicità dose-limit. Il protocollo permette l'escalation alle Coorti 5–7 (25, 50, 100 µg/kg/giorno) se necessario. Lo studio prevede fino a circa 14 pazienti e valuterà sicurezza, PK/PD, espansione delle NK e attività clinica. Il prossimo aggiornamento è atteso nel 1° trimestre 2026.
GT Biopharma (NASDAQ: GTBP) informó que la revisión formal de seguridad de la Cohorte 3 (5 µg/kg/día) en el ensayo de Fase 1 GTB-3650 finalizó sin problemas de seguridad o tolerabilidad, lo que permite avanzar a la Cohorte 4 (10 µg/kg/día). Seis pacientes han sido tratados en las Cohortes 1–3. Se espera iniciar la dosificación de la Cohorte 4 en las próximas semanas y se considera que refleja más adecuadamente un posible umbral de eficacia, basado en tendencias positivas en múltiples biomarcadores inmunológicos y la ausencia de toxicidad dosis‑limitante. El protocolo permite escalar a las Cohortes 5–7 (25, 50, 100 µg/kg/día) si es necesario. El ensayo planea incluir hasta ~14 pacientes y evaluará seguridad, PK/PD, expansión de NK y actividad clínica. La próxima actualización se espera para el primer trimestre de 2026.
GT Biopharma (NASDAQ: GTBP)는 1상 GTB-3650 임상에서 코호트 3(5 µg/kg/일)의 정Formal 안전성 검토가 안전성 또는 내약성 문제 없이 마무리되어 코호트 4(10 µg/kg/일)로의 진행이 가능해졌다고 발표했다. 코호트 1–3에서 총 6명의 환자가 치료를 받았다. 코호트 4의 투여는 향후 몇 주 내에 시작될 예정이며, 다수의 면역생물지표에서 긍정적 흐름과 용량 제한 독성의 부재를 바탕으로 잠재적 효능 임계값을 더 잘 반영하는 것으로 간주된다. 프로토콜은 필요 시 코호트 5–7(25, 50, 100 µg/kg/일)으로의 증가를 허용한다. 이 임상은 최대 약 14명의 환자를 목표로 하며 안전성, PK/PD, NK 세포 확장, 임상 활성을 평가할 것이다. 다음 업데이트는 2026년 1분기에 기대된다.
GT Biopharma (NASDAQ: GTBP) a annoncé que l’évaluation formelle de la sécurité de la cohorte 3 (5 µg/kg/jour) dans l’essai de phase 1 GTB-3650 s’est terminée sans problèmes de sécurité ou de tolérance, permettant d’avancer vers la cohorte 4 (10 µg/kg/jour). Six patients ont été traités dans les Cohortes 1–3. Le démarrage du traitement de la cohorte 4 est prévu dans les prochaines semaines et est jugé plus représentatif d’un seuil potentiel d’efficacité, sur la base de tendances positives dans plusieurs biomarqueurs immunologiques et de l’absence de toxicité limitante par dose. Le protocole autorise une escalade vers les Cohortes 5–7 (25, 50, 100 µg/kg/jour) si nécessaire. L’essai prévoit jusqu’à environ 14 patients et évaluera la sécurité, le PK/PD, l’expansion des NK et l’activité clinique. La prochaine mise à jour est attendue au premier trimestre 2026.
GT Biopharma (NASDAQ: GTBP) berichtete, dass die formale Sicherheitsprüfung der Kohorte 3 (5 µg/kg/Tag) in der Phase-1-Studie GTB-3650 ohne Sicherheits- oder Verträglichkeitsprobleme abgeschlossen wurde, was zum Voranschreiten zur Kohorte 4 (10 µg/kg/Tag) führt. Sechs Patienten wurden in den Kohorten 1–3 behandelt. Die Verabreichung der Kohorte 4 soll in den kommenden Wochen beginnen und wird als besser geeignet angesehen, einen potenziellen Wirksamkeitsschwelle anhand positiver Trends in mehreren immunologischen Biomarkern und dem Fehlen dosislimitierender Toxizität zu reflektieren. Das Protokoll erlaubt eine Eskalation zu Kohorten 5–7 (25, 50, 100 µg/kg/Tag), falls erforderlich. Die Studie plant bis zu etwa 14 Patienten und wird Sicherheit, PK/PD, NK-Zellexpansion und klinische Aktivität bewerten. Die nächste Aktualisierung wird im ersten Quartal 2026 erwartet.
GT Biopharma (NASDAQ: GTBP) أبلغت أن المراجعة الرسمية للسلامة للـ المجموعة 3 (5 µg/kg/يومًا) في تجربة المرحلة الأولى GTB-3650 انتهت بدون مشكلات سلامة أو تحمّل، مما أتاح التقدم إلى المجموعة 4 (10 µg/kg/يومًا). تم علاج ستة مرضى عبر المجاميع 1–3. من المتوقع أن يبدأ إعطاء الجرعة للمجموعة 4 خلال الأسابيع القادمة وتُعتبر أكثر تمثيلًا لعتبة محتملة للفعالية بناءً على اتجاهات إيجابية في عدة مؤشرات مناعية وغياب السمية التي تعتمد على الجرعة. يسمح البروتوكول بالتصعيد إلى المجموعات 5–7 (25، 50، 100 µg/kg/يومًا) إذا لزم الأمر. تخطط التجربة لإشراك حتى حوالي 14 مريضًا وستقيّم السلامة وPK/PD وتوسع NK والنشاط السريري. التحديث التالي متوقع في الربع الأول من 2026.
- Cohort 3 safety review showed no safety or tolerability issues
- Progression to Cohort 4 (10 µg/kg/day) initiated screening
- Six patients treated across Cohorts 1–3
- Protocol allows escalation up to 100 µg/kg/day
- Only 6 of ~14 planned patients treated, early-stage dataset
Insights
GT Biopharma cleared a formal safety review for Cohort 3 and is advancing to Cohort 4 at 10 ug/kg/day; next update expected in
GTB-3650 advances the Phase 1 dose-escalation by moving from Cohort 3 to Cohort 4 after a formal safety review reported no safety or tolerability issues in the six patients treated across Cohorts 1–3. The trial tests sequential dose cohorts from 1.25 ug/kg/day up to 100 ug/kg/day, measures safety, pharmacokinetics, pharmacodynamics, endogenous NK cell expansion and clinical activity, and doses in two-week on/off cycles for up to four months.
Key dependencies and risks include the need for continued absence of dose-limiting toxicities as dosing increases and confirmation that the reported positive trends in immunologic biomarkers translate to clinical benefit. The protocol allows three higher cohorts (Cohorts 5–7 at 25, 50 and 100 ug/kg/day) which will determine tolerability at potential efficacy-relevant exposures; escalation could reveal new adverse effects not seen at lower doses.
Watch for the company’s next formal update in
The formal safety review of Cohort 3 (5ug/kg/day) has been successfully completed with no safety or tolerability issues observed, allowing advancement into Cohort 4 with a dose of 10 ug/kg/day
Actively screening patients for Cohort 4; anticipate initiation of dosing in the coming weeks
Cohort 4 dose is potentially more reflective of the clinical efficacy threshold given positive trend in observations on multiple immunological biomarkers from the previous six patients in Cohorts 1 through 3, the absence of dose limiting toxicities, and the associated lower dose levels
Next update expected in Q1 2026, as well as continued dose escalation (up to 100ug/kg/day) in 3 additional cohorts if necessary
SAN FRANCISCO, CALIFORNIA, Oct. 23, 2025 (GLOBE NEWSWIRE) -- GT Biopharma, Inc. (the “Company”) (NASDAQ: GTBP), a clinical stage immuno-oncology company focused on developing innovative therapeutics based on the Company's proprietary TriKE® natural killer (NK) cell engager platform, today announced successful completion of the Cohort 3 formal safety review with no safety or tolerability issues observed and advancement into Cohort 4 of its Phase 1 dose escalation trial evaluating GTB-3650 for the treatment of relapsed or refractory (r/r) CD33 expressing hematologic malignancies.
The six patients in Cohorts 1 through 3 have been successfully treated with GTB-3650 and the formal safety review of Cohort 3 showed no safety or tolerability issues observed. This has allowed progression to actively screening patients for Cohort 4. With a dose of 10 ug/kg/day, Cohort 4 is more reflective of the potential efficacy threshold. The Phase 1 trial protocol allows for three additional cohorts with much higher dose levels ranging from 25 ug/kg/day with Cohort 5, 50 ug/kg/day with Cohort 6 and 100 ug/kg/day for Cohort 7, if necessary. The company anticipates providing its next update on the trial in Q1 2026.
The Phase 1 trial will evaluate of GTB-3650 in up to approximately 14 patients (two patients in each of seven cohorts), with doses ranging from 1.25 ug/kg/day in Cohort 1 to 100 ug/kg/day in Cohort 7. GTB-3650 is dosed in two-week blocks, two weeks on and two weeks off (defining a treatment cycle), for up to four months based on clinical benefit. The trial will assess safety, pharmacokinetics, pharmacodynamics, in vivo expansion of endogenous patient NK cells and clinical activity. More details can be found on clinicaltrials.gov with the identifier: NCT06594445.
About GT Biopharma, Inc.
GT Biopharma, Inc. is a clinical stage biopharmaceutical company focused on the development and commercialization of immuno-oncology therapeutic products based on our proprietary TriKE® NK cell engager platform. Our TriKE® platform is designed to harness and enhance the cancer killing abilities of a patient’s immune system’s natural killer cells. GT Biopharma has an exclusive worldwide license agreement with the University of Minnesota to further develop and commercialize therapies using TriKE® technology. For more information, please visit gtbiopharma.com.
Forward-Looking Statements
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TriKE® is a registered trademark owned by GT Biopharma, Inc.
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FAQ
What did GTBP announce about the GTB-3650 Phase 1 Cohort 3 safety review on October 23, 2025?
When will GTBP begin dosing Cohort 4 (10 µg/kg/day) in the GTB-3650 trial?
How many patients have been treated so far in GTBP's GTB-3650 Phase 1 trial (NCT06594445)?
What dose levels could GTBP escalate to after Cohort 4 in the GTB-3650 trial?
What endpoints will the GTB-3650 Phase 1 trial assess for GTBP (GTBP)?
When is GT Biopharma expected to provide the next update on the GTB-3650 trial?
