FDA approves Lilly’s LARTRUVO in combination with doxorubicin for soft tissue sarcoma

LARTRUVO's indication is approved under Accelerated Approval, and is based on data from the Phase 2 portion of the pivotal JGDG trial.

Continued approval for this indication may be contingent upon verification and description of clinical benefit in a confirmatory trial.

LARTRUVO, in combination with doxorubicin, is the first FDA-approved front-line therapy for STS in four decades. The confirmatory Phase 3 trial, ANNOUNCE, is fully enrolled.

"LARTRUVO represents an important step forward in soft tissue sarcoma treatment," said William D. Tap, M.D., chief of the sarcoma medical oncology services at Memorial Sloan Kettering Cancer Center in New York and the principal investigator of the JGDG registration trial.

"We are pleased with this approval, which will provide patients with a treatment option that offers new hope in their battle against this difficult disease."

Soft tissue sarcoma is a complex disease with multiple subtypes, making it hard to diagnose and difficult to treat. For decades, there have been no first-line therapeutic advancements for STS that have improved overall survival (OS).

According to the American Cancer Society, in 2015, there were an estimated 12,000 new STS cases diagnosed and nearly 5,000 deaths in the U.S. alone, representing an unmet medical need.

LARTRUVO is the first monoclonal antibody approved to treat STS. It also received Fast Track, Orphan Drug and Breakthrough Therapy designations from the FDA for this indication, and was reviewed and approved under the FDA's Accelerated Approval program. This program allows for earlier approval of drugs that treat serious conditions and that fill an unmet medical need.

Richard Gaynor, M.D., senior vice president, product development and medical affairs for Lilly Oncology, said: "The approval of LARTRUVO is based on an encouraging and positive study for patients, and represents progress in soft tissue sarcoma treatment. For the first time in four decades, we now have a combination regimen – LARTRUVO and doxorubicin – that offers progress over doxorubicin alone in the front-line setting, by improving overall survival for people with soft tissue sarcoma.

"This continues our commitment to discovering new ways to treat cancer, including for people who have rare types of cancer."

"The entire sarcoma patient community is excited to have an innovative medicine approved for the treatment of advanced soft tissue sarcoma," said Bert E. Thomas IV, PhD, MBA, CEO of the Sarcoma Foundation of America. "We are confident that the approval of LARTRUVO may help these patients live longer."

The approval of LARTRUVO is based on the results of JGDG, an open-label, randomized, active-controlled study of 133 patients, which compared LARTRUVO, in combination with doxorubicin chemotherapy, to doxorubicin alone in patients with STS with a histologic subtype for which an anthracycline-containing regimen was appropriate and which is not amenable to curative treatment with surgery or radiotherapy. The efficacy outcome measures were OS, progression-free survival (PFS), and objective response rate (ORR).

Median OS was improved by 11.8 months in patients randomized to receive LARTRUVO plus doxorubicin compared to patients randomized to doxorubicin alone, and was statistically significant.

Median OS was 26.5 months (95% CI: 20.9, 31.7) on the LARTRUVO-doxorubicin arm compared to 14.7 months (95% CI: 9.2, 17.1) on the doxorubicin-only arm (stratified hazard ratio [HR], 0.52; 95% CI: 0.34, 0.79, < 0.05).

The study met its prespecified protocol-defined endpoint for PFS. Patients treated on the LARTRUVO and doxorubicin arm achieved 8.2 months (95% CI: 5.5, 9.8) of median PFS compared to 4.4 months (95% CI: 3.1, 7.4) on the doxorubicin-only arm (stratified hazard ratio [HR], 0.74; 95% CI: 0.46, 1.19), based on independent review. The number of events at the time of analysis was 37 (56%) on the LARTRUVO-doxorubicin arm and 34 (51%) on the doxorubicin-only arm.

The number of deaths at the time of analysis was 39 (59%) on the LARTRUVO-doxorubicin arm and 52 (78%) on the doxorubicin-only arm. Objective response rate (ORR), based on independent review and defined as complete response (CR) plus partial response (PR), was also assessed with an ORR of 18.2 percent (95% CI: 9.8, 29.6) (CR, 4.5%; PR, 13.6%) on the LARTRUVO-doxorubicin arm and 7.5 percent (95% CI: 2.5, 16.6) (CR, 1.5%; PR, 6%) on the doxorubicin-only arm.   

The labeling for LARTRUVO contains Warnings and Precautions for infusion-related reactions and embryo-fetal toxicity. The most commonly reported adverse reactions (all grades) occurring in ≥20 percent of patients receiving LARTRUVO plus doxorubicin versus doxorubicin alone were nausea (73% vs 52%), fatigue (69% vs 69%), musculoskeletal pain (64% vs 25%), mucositis (53% vs 35%), vomiting (45% vs 19%), diarrhea (34% vs 23%) and headache (20% vs 9%).

The most common laboratory abnormalities (all grades) occurring in ≥20% of patients receiving LARTRUVO plus doxorubicin versus doxorubicin alone were lymphopenia (77% vs 73%), neutropenia (65% vs 63%), thrombocytopenia (63% vs 44%), hyperglycemia (52% vs 28%), elevated aPTT (33% vs 13%), hypokalemia (21% vs 15%) and hypophosphatemia (21% vs 7%). Febrile neutropenia was reported in 13% of LARTRUVO plus doxorubicin-treated patients versus 12% of doxorubicin-treated patients.

Adverse reactions resulting in permanent discontinuation of LARTRUVO occurred in 8% (5/64) of patients. The most common adverse reaction leading to LARTRUVO discontinuation was infusion-related reaction (3%).

Dose reductions of LARTRUVO for adverse reactions occurred in 25% (16/64) of patients; the most common adverse reaction leading to dose reduction was Grade 3 or 4 neutropenia (20%). Dose delays of LARTRUVO for adverse reactions occurred in 52% (33/64) of patients; the most common adverse reactions resulting in dose delays were neutropenia (33%), thrombocytopenia (8%) and anemia (5%).