Pegylated Liposomal Doxorubicin (PLD) in Combination with Bortezomib (B) May Provide Therapeutic Advantage for High-Risk Multiple Myeloma Patients Relapsing within 12 Months of Stem Cell Transplant.

Background: Patients (Pts) with multiple myeloma (MM) who relapse within 12 months of autologous stem cell transplantation (SCT) have a poor prognosis. As reported by Mahmood et al. (ASCO 2007), of 432 pts who received SCT at the Mayo Clinic between 1994-2005, those with early relapse within 12 months (94/432- 22%) showed poorer median overall survival. Kaplan-Meier estimates of 12-month survival from the date of first relapse were 37% for pts relapsing within 12 months after SCT as compared to 85% for those relapsing after 12 months. In that study, pts had received regimens other than B. In a recent report of a large, phase III study (DOXIL-MMY3001), the combination of PLD+B improved time to progression (TTP) as compared to B alone (Orlowski et al. JCO 2007). The present analysis examined the 12-month post-randomization survival of patients who had early (<12 months) vs. late (12 months) relapse following SCT, as well as the effect of PLD+B vs. B alone in pts who had relapsed early. Methods: This was a retrospective analysis of 646 pts who received intravenous B, 1.3 mg/m2 on days 1,4,8 and 11 of every 21-day cycle PLD, 30 mg/m2 on day 4. Results: 359 pts had previously received transplant, 114 (32%) of whom relapsed within 12 months from SCT. The median age, gender distribution, time from diagnosis trial enrollment, measures of disease burden (M-Protein levels and B2M) and renal function were comparable between the early and late relapse groups. There was no difference in overall response rates [complete + partial response (CR+PR)] or very good PR (VGPR) rates between the two groups, or between treatment arms within each group. There was no significant difference in TTP between early vs. late relapse groups (HR=0.94). 12-month survival from randomization was significantly lower in the early relapse group as compared to late relapse (83% vs. 92% respectively, p=0.009). However, within the early relapse group 12-months post-randomization survival rate was significantly superior following treatment with PLD+B as compared to B alone [52/56 patients (93%) vs. 43/58 patients (74%) respectively, p=0.01]. Correspondingly, TTP was better in this group with PLD+B vs. B alone (276 days vs. 205 days respectively, p=0.13). Overall, the toxicity profiles of the combination and B alone were comparable regardless of early or late relapse following SCT. Conclusions: The present analysis of the MMY3001 study corroborates the prior Mayo observation of lower survival in MM pts relapsing within 12 months of SCT. Importantly, it demonstrates that PLD+B may provide a therapeutic advantage for high-risk MM pts with early relapse following SCT.

Abstract #2730 appears in Blood, Volume 110, issue 11, November 16, 2007

Keywords: Doxil|Velcade|Post-Transplant

Disclosure: Employment: S. Mundle and S. Zhuang are employees of Johnson Johnson. Consultancy: J. Blade, Johnson Johnson; J. San Miguel, Johnson Johnson, Celgene, Pharmion; P. Sonneveld, Johnson Johnson. Ownership Interests:; S. Mundle and S. Zhuang own stock in Johnson Johnson. Research Funding: S. Kumar, Millennium, Celgene, Gemzyne; J. Blade, Johnson Johnson. Honoraria Information: J. Blade, Johnson Johnson; J. San Miguel, Johnson Johnson, Celgene, Pharmion; A. Spencer, Johnson Johnson, JL Harousseau, Millennium. Membership Information: J. San Miguel, Johnson Johnson, Celgene, Pharmion; A. Spencer, Johnson Johnson, JL Harousseau, Johnson Johnson; RZ Orlowski, Millennium and Johnson Johnson.

Sunday, December 9, 2007 6:00 PM

Session Info: Poster Session: Myeloma: Relapsed and Refractory Multiple Myeloma (6:00 p.m.-8:00 p.m.)