リンパ腫の新たな治療法はCHOPよりも有効性が高い （Abstract # 3）

リンパ腫に対するベンダムスチン療法は標準的な治療法よりも有効性が高く副作用が少ない
Bendamustine regimen more effective for lymphoma than standard therapy with fewer side effects
第48回American Society of Clinical Oncology学会で発表された多施設第3相試験の結果、緩徐進行性リンパ腫およびマントル細胞リンパ腫患者において、bendamustineとリツキシマブによる併用化学療法は標準治療よりも無増悪生存期間を倍の6年近くにまで延長することが示された。研究者らは未治療の緩徐進行性非ホジキンリンパ腫またはマントル細胞リンパ腫患者514人を、ベバシズマブ/リツキシマブ（B-R）またはリツキシマブとシクロホスファミド、ドキソルビシン、ビンクリスチンおよびプレドニゾロン（R-CHOP）のいずれかを投与される群に無作為に割り付け、無増悪生存期間を比較した。追跡期間中央値45か月後の無増悪生存期間（PFS）中央値は、B-R群で69.5か月であったのに対しR-CHOP群では31.2か月であった。全生存期間は両群間で差がなく、その理由の一部は疾患が増悪し続けたR-CHOP患者の半数はB-Rを受けることを許可されたためであり、一部は緩徐進行性リンパ腫の生存期間は非常に長い傾向にあるためであった。そのためPFSが最も信頼できる臨床上の有益性や患者のQOLの指標となっている。Bendamustine療法は副作用も少なかった。
Full Text

Long-term results from a multicenter Phase III study presented at the ASCO's 48th Annual Meeting show that initial combination chemotherapy with bendamustine and rituximab more than doubled progression-free survival, to nearly six years, compared with standard R-CHOP therapy among patients with indolent lymphoma and mantle cell lymphoma. The bendamustine regimen was also associated with fewer side effects.

"This is the first randomized clinical trial to compare bendamustine and rituximab with a standard chemotherapy regimen for these more challenging types of lymphoma, and it clearly shows that the bendamustine-based regimen is more effective and less toxic," said Mathias J. Rummel, M.D., Ph.D., Professor of Medicine at the University Hospital Giessen in Germany and lead author of the study. "Just as important, bendamustine-based therapy allowed patients to have a better quality of life while undergoing therapy. These long-term findings should be strong enough to change clinical practice."

R-CHOP, a standard chemotherapy regimen for many non-Hodgkin lymphomas, includes the targeted therapy rituximab plus the drugs cyclophosphamide, doxorubicin, vincristine and prednisone. Bendamustine has been used for decades in Europe (it was developed in Eastern Europe), but only became available in the U.S. in 2008. While many U.S. doctors already use the bendamustine-based regimen based on earlier data from this trial, uptake has not been universal.

The investigators compared progression-free survival between 514 patients with previously untreated indolent non-Hodgkin or mantle cell lymphomas who were randomly assigned to receive either bendamustine/rituximab (B-R) or R-CHOP. After a median follow-up of 45 months, median progression-free survival (PFS) was 69.5 months in the B-R group versus 31.2 months for the R-CHOP group. Overall survival did not differ between the two groups, partly because nearly half of the R-CHOP patients whose disease continued to progress were then permitted to receive B-R, and partly because survival for indolent lymphomas tends to be very long, making PFS the most reliable measure of clinical benefit and patient quality of life.

While there was a higher incidence of mild skin reactions in the B-R group, there was no hair loss and a lower incidence of nerve toxicity and infections, compared with the R-CHOP group. Moderate to severe declines in neutrophil counts (a type of white blood cell) occurred in 69 percent of the R-CHOP patients and 29 percent of the B-R group; G-CSF treatment (a drug used to boost neutrophil counts) was needed after 20 percent of R-CHOP chemotherapy cycles, but after only 4 percent of B-R cycles.