LEGN CARVYKTI: 50% PFS at 5 Years After One Infusion

Legend Biotech (LEGN) reported five-year follow-up from the Phase 2 CARTITUDE-2 study showing that 10 of 20 patients (50%) with relapsed/refractory multiple myeloma were alive and progression-free five years after a single CARVYKTI infusion, with no further anti-myeloma therapy. The data were presented September 25 at the International Myeloma Society annual meeting in Glasgow (press release).

CARVYKTI (ciltacabtagene autoleucel, or cilta-cel) is a BCMA-directed CAR-T therapy Legend co-develops 50/50 with Johnson & Johnson. The Cohort A patients had received one to three prior lines of therapy and were refractory to lenalidomide. At a median follow-up of 60.7 months, median progression-free survival reached 60.5 months, median overall survival was not reached, and the five-year survival rate was 69.2%. The earlier CARTITUDE-1 study in heavily pretreated patients showed 33% (32 of 97) remained progression-free at five years, so the 50% cohort result points to better outcomes when CARVYKTI is used earlier in the disease. CARVYKTI was first approved in 2022 and expanded to second-line use in April 2024.

The treatment is built from a patient’s own T cells, which are reprogrammed in a lab to recognize and kill BCMA-expressing myeloma cells, then reinfused once. A single dose that keeps half of patients progression-free and off therapy for five years argues for moving CARVYKTI earlier in the treatment sequence, before later-line disease erodes bone marrow and T-cell fitness. The contrast matters against BCMA bispecific antibodies like Tecvayli and Talvey, which require continuous dosing rather than a one-time infusion. That trade-off is covered in the CAR-T versus bispecifics analysis.

The caveat is sample size. Cohort A enrolled 20 patients in a Phase 2 basket study, not a confirmatory trial. The registrational gold standard is CARTITUDE-4, the Phase 3 trial that already showed an overall-survival benefit versus standard of care. CARVYKTI is the first and only CAR-T in multiple myeloma to show that survival benefit, which is why Legend frames the cohort as evidence of “curative potential” rather than proof. Longer follow-up also surfaced one new case of acute myeloid leukemia and two deaths since the prior 30-month analysis, a reminder that even durable remissions carry real safety trade-offs. Rival BMS’s Abecma has lagged on durability, adding to the one-time-infusion argument.

LEGN closed September 25 at $19.11 for a $3.7 billion market cap, about three times Legend’s half of a CAR-T franchise now running above $2.6 billion in annual sales. Multiple myeloma will be diagnosed in more than 36,000 people in the U.S. this year. What to watch next: longer CARTITUDE-4 data and Legend’s push to move CARVYKTI into newly diagnosed myeloma, where the durable-remission argument would matter most.

What It Means for the Trade

The setup here is a small-cap stock with a stake in a large and growing franchise. At $19.11, Legend trades at roughly three times its half of a CARVYKTI franchise running above $2.6 billion a year, which means the market is paying for the existing profit share and getting the earlier-line and front-line optionality at a steep discount — that is the bull case in one line. The CARTITUDE-2 data is the supporting evidence for it: 50% progression-free at five years in lenalidomide-refractory patients after one to three prior lines, versus 33% in the heavily pretreated CARTITUDE-1 population, argues CARVYKTI’s economics improve as it moves earlier. The near-term catalysts are continued CARTITUDE-4 follow-up and any progress in newly diagnosed myeloma, where a durable-remission claim would carry the most weight. This is a position-sizing story, not a moonshot — the franchise already exists and is growing.

Mechanism and Market Context

CARVYKTI’s core advantage over the BCMA bispecifics is permanence. Tecvayli and Talvey require continuous dosing to keep disease suppressed; a single infusion that keeps half of cohort A patients off all anti-myeloma therapy for five years is a different value proposition for both patients and payers. Moving earlier in the line sequence is not just a market-share question — later-line disease erodes bone marrow reserve and T-cell fitness, the raw material the CAR-T manufacturing process depends on. One-time infusion versus chronic therapy is also why BMS’s Abecma has lagged on durability comparisons, and why J&J and Legend are pushing the sequencing question hard.

Risks and What Could Go Wrong

1. Cohort A is 20 patients in a Phase 2 basket — the durability signal is hypothesis-grade until confirmatory data land.
2. Longer follow-up surfaced one new AML case and two deaths, a reminder that deep remissions carry real safety trade-offs.
3. J&J leads commercialization on a 50/50 split, so Legend’s economics depend on a partner’s priorities.
4. Off-the-shelf bispecifics keep improving on convenience, and CAR-T’s manufacturing complexity is a persistent commercial friction.