TLD-1, a novel liposomal doxorubicin, in patients with advanced solid tumors: Dose escalation and expansion part of a multicenter open-label phase I trial (SAKK 65/16)

BACKGROUND

TLD-1 is a novel liposomal doxorubicin that compared favorably to conventional doxorubicin liposomal formulations in preclinical models. This phase I first-in-human study aimed to define the maximum tolerated dose (MTD), recommended phase 2 dose (RP2D), safety and preliminary activity of TLD-1 in patients with advanced solid tumors.

PATIENTS AND METHODS

We recruited patients with advanced solid tumors who failed standard therapy and received up to 3 prior lines of palliative systemic chemotherapy. TLD-1 was administered intravenously every 3 weeks up to a maximum of 9 cycles (6 for patients with prior anthracyclines) from a starting dose of 10 mg/m2, according to an accelerated titration design followed by a modified continual reassessment method.

RESULTS

30 patients were enrolled between November 2018 and May 2021. No dose-limiting toxicities (DLT) were observed. Maximum administered dose of TLD-1 was 45 mg/m2, RP2D was defined at 40 mg/m2. Most frequent treatment-related adverse events (TRAE) of any grade included palmar-plantar erythrodysesthesia (PPE) (50% of patients), oral mucositis (50%), fatigue (30%) and skin rash (26.7%). Most common G3 TRAE included PPE in 4 patients (13.3%) and oral mucositis in 2 (6.7%). Overall objective response rate was 10% in the whole population and 23.1% among 13 patients with breast cancer; median time-to-treatment failure was 2.7 months. TLD-1 exhibit linear pharmacokinetics, with a median terminal half-life of 95 h.

CONCLUSIONS

The new liposomal doxorubicin formulation TLD-1 showed a favourable safety profile and antitumor activity, particularly in breast cancer. RP2D was defined at 40 mg/m2 administered every 3 weeks. (NCT03387917).

TLD-1, a novel liposomal doxorubicin, in patients (pts) with advanced solid tumors: Dose escalation and expansion part of a multicenter open-label phase I trial (SAKK 65/16)

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Background: TLD-1 is a novel liposomal doxorubicin that compared favorably to conventional liposomal formulations of doxorubicin in preclinical in vivo mouse breast cancer models. This phase I first-in-human trial is aiming to determine the recommended phase II dose (RP2D), toxicity profile, pharmacokinetics and preliminary activity. Methods: Patients with a maximum of 3 prior lines of systemic chemotherapy and preferably anthracycline-sensitive disease were eligible. TLD-1 was administered on day 1 iv over 60-90 minutes (depending on individual dose) q 21 days, for up to 6 or 9 cycles (according to prior anthracycline-exposure) with premedication of 8mg dexamethasone. Dose escalation with dose levels (DL) 1-7 of 10, 16, 23, 30, 35, 40 and 45mg/m2 started with an accelerated titration design, treating one pt at each DL up to DL6 (40mg/m2) followed by a modified continual reassessment method at DL7 due to observed toxicity. Results: 30 pts (F:M = 24:6) have been treated, one each at DLs 1-6, 15 pts at DL7 and an additional 9 pts at DL6. Most frequent tumor types included breast (n = 13), ovarian (n = 6), cervical cancer (n = 2) and cholangiocarcinoma (n = 2). Median age was 67.5 years (range:38-83), 13 pts were exposed to prior anthracyclines. The median number of cycles was 4 (range:1-9). No dose-limiting toxicities (DLT) occurred during cycle 1. At DLs 1 to 5, no treatment-related G3 AEs (TRAE) were observed. At DL6, there was one case of mucositis G3, one of palmar-plantar-erythrodysesthesia (PPE) G3 and one of anemia and neutropenia G3 each. One patient with pre-existing valvular cardiopathy developed symptoms of heart-failure G3 after 8 cycles. Echocardiography showed severe mitral regurgitation with normal LV-EF. In addition one case of urinary-tract infection G3 was seen. Dose-modifications or -delays due to AEs occurred in 7/50 cycles. At DL7, one case of mucositis G3, 3 events of PPE G3 and one case of fatigue G3 were reported. In addition, one case of infection with shingles occurred. Dose-modifications or -delays due to AEs occurred in 12/61 cycles. Shingles and heart failure were reported as SAEs. All toxicities listed above were categorized as TRAE. 29/30 pts were evaluable for response. Three breast cancer pts had a partial response, 2 at DL7 and 1 at DL6, 14 pts had stable disease. Conclusions: No DLT was observed up to DL7. RP2D was defined at 40mg/m2 due to cumulative PPE G3 at DL7. The trial is ongoing with a comparative PK-part evaluating the two iv liposomal formulations of doxorubicin TLD-1 and Caelyx. Clinical trial information: NCT03387917.

Abstract 174: Preclinical activity of new liposomal formulation of doxorubicin (TLD-1)

Background: InnoMedica is a young company with focus on clinical translation of nanomedicine. The company employs its own manufacturing technology that gives rise to a novel liposome platform. The platform allows for specific shaping of nanosurfaces. This leads to a myriad of different particle designs with highly distinct biological functions. In a first approach, the lead-formulation TLD-1 (targeted liposomal doxorubicin) was developed in order to ameliorate chemotherapeutic outcome for patients, taking into account the patterns of biodistribution in the entire organism as well as nanoparticle-cell interactions and subcellular localisation.

Methods: Pharmacologic properties of TLD-1 were investigated in vitro and in vivo. Human ovarian cancer cells A2780 were cultured in both 2D and 3D settings and antineoplastic activity of different formulations of doxorubicin was measured by quantification of cell viability. The same formulations were also compared in three animal models of cancer including murine breast cancer 4T1, human breast cancer MDA-MB231, and A2780. MDA-MB231 and A2780 cells were grown in vitro and injected subcutaneously (sc) in immunodeficient mice (Athymic Nude-Foxn1nu). 4T1 cells were injected either sc or in the mammary fat pad of immunocompetent mice (BALB/c). The different drug products were injected intravenously twice weekly for a total of three weeks. Activity was determined with caliper measurements of tumor diameters every three days. Animal body weight was recorded as index of toxicity. Doxorubicin was determined in plasma and tissues by HPLC-MS.

Results: In 2D and 3D cell culture assays, TLD-1 showed a marked increase in cytotoxicity compared to Caelyx and was close to free drug. In all three animal models, TLD-1 showed activity superior to that of free doxorubicin given at the same dose and compared well to Caelyx both in terms of activity and toxicity.

Conclusions: A couple of nanoparticulate features of TLD-1 liposomes are believed to attribute to the difference in antitumor activity. Cytotoxicity data from cell culture experiments indicate that TLD-1 liposomes are readily taken up by cancer cells and release their drug load into the cytoplasm. Commercial liposomes as in Caelyx seem to largely remain outside of cancer cells. In sum, TLD-1 is a novel and highly active antineoplastic nanodrug that has the potential to outperform free drug as well as commercial liposomal formulations of doxorubicin.

Citation Format: Massimo Broggini, Federica Guffanti, Roberta Affatato, Lavinia Morosi, Patrick Buschor, Christoph Matthieu, Florian Weiss, Andreas Konig, Peter Halbherr, Stefan Halbherr. Preclinical activity of new liposomal formulation of doxorubicin (TLD-1) [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 174. doi:10.1158/1538-7445.AM2017-174