MDACC has, for the first time, given their experience of TKI
6 \9 e% p$ x. O) Bdiscontinuation. The doctors at MDACC look at 26 patients who
( `, W2 t: e$ k& |discontinued therapy from 2003-2012 for various reasons. These reasons1 R7 }2 E4 _9 y0 m
include long time in CMR, adverse side-effects, pregnancy and financial
; [; ] D4 t+ B2 D- a7 ^- |constraints. Please note that 17 patients discontinued therapy in CMR
" u6 l. ]6 X v0 T8 v" M1 p) Eand the rest in MMR. Of the patients in CMR who discontinued therapy,9 ^. }- g4 y ?: J* Z# n6 P1 b
47% had molecular relapse. Those in CMR who discontinued and had taken
# z! l. @( V+ }7 t& ~$ Aprior Interferon to a TKI, 50% relapsed. Also note that of these 26* M4 O6 i) X% y. t F% s
patients, most had been treated with high dose Gleevec.
" U/ u B) y; O- p h- \1 y/ }" h3 o i% k/ z7 c
"All patients discontinued therapy in CML-CP, all in CCyR, of them, 17
~' q% G5 g' Y(65%) had undetectable transcripts, 2 (8%) had MR4.5, and 7 (27%) MMR.
& ~" V+ A) K. \! K& ]( r. ZThe median duration of CMR before TKI cessation was 62 mos, (0- 118).' v. t, q+ B. ^# J
The median duration of total TKI therapy was 101 mos (3- 135)."; n$ i: e' R+ C" g
5 h& K% f" W: dTherefore, the median time in CMR before discontinuation was about 5$ Y2 M8 h" e9 z
years. The median follow-up is only 11 months. The median time for# L" ?* N4 p" ^+ c5 g d
molecular relapse of 8 patients who had been in CMR was 4 months and+ F. S% t- R* I a8 s* [
they relapsed with median PCR value of 0.01 on the International Scale.4 @% g" G# j+ a& S4 ]
h! m; a/ h& h, R
Of the 7 patients who discontinued when in MMR, 4 remained in MMR at a3 n/ @" r% u* p- ~, Y1 F9 ~0 w# R* |
median follow-up of 21 months, 1 remained in CCR, 1 in active disease9 m0 ^% x7 W# y2 s& }& M# V
and 1 transformed to accelerated phase off drugs. Therefore, from this
% F- X2 z! T% z) l) r# Q7 Vdata, scarce as it is, there is a risk of transformation to advanced8 \1 U( j3 ]8 J0 }# j! m
disease if one discontinues drugs in MMR.
' ~; R# d! f" ]) C
! z. U& g! H- B5 ?3 U+ S2 patients were PCRU (4.5 log machine) and these patients relapsed4 G4 y. @( W0 b; @, K& R& S5 j6 G7 `
into MMR when drugs were discontinued.- Y2 Z/ e, ?- o! g
9 B8 H4 S& V+ V* _* {' e
Seven pts with relapse were treated again with TKI, 3 with nilotinib,
! ]8 ?; e4 Y% G2 with dasatinib, and one each with imatinib and bosutinib (the latter
& M; I) y: I$ ^& \in AP). After a median of 13 months on therapy (range 4-52) all patients7 [; H/ a6 _1 S, B5 F
improved their response, 5 with CMR and 2 MMR (including the pt that had8 o" f) ?' [5 O. h; Y" w
transformed to AP). They do not say why all patients were not retreated6 m7 B+ Q6 t3 F, \+ S
with imatinib and had to take Nilotinib and Dasatinib. Also, note that
, z; b5 Y- l4 i! ` [& m R/ }one did not regain CMR at the 13th month mark though it is good news( ]. w: M7 ]: J7 M3 W8 Q
that 5 did. It may take some time to regain CMR for some who have gone
" C0 K& [2 R3 E4 Qoff drugs and relapsed. However, from our own list experiences, some
" ]' L- g. T7 z5 n `4 ahad regained CMR fast when they retook the TKI.: d3 ?% D5 _, Z
( f+ m/ u' i% ~' i* v' H$ y
The doctors conclude that treatment discontinuation is experimental% W# {+ k' M. o) f. i
and cannot be recommended at this stage as a standard procedure.3 o- G$ M3 f1 E3 t% P
3 s' ?- n' u# J; J! d: ?Best Wishes,
y$ Y. ^' V* w! e* U) E
7 z3 G+ m- C* R- S0 V G) XAnjana
8 T; n p. [1 J, a2 e3 S
4 Q7 W$ A3 G e) o j: } }( {: v, D4 j& L a: Z2 a* O$ y
+ e$ y! U) ^$ ]- r V: t8 `- Y h: H; @1 M @& ]
# x2 L$ m/ U4 Y6 j$ V* y- H; N' k( i, `1 B, S9 q( B
1 D2 [0 `$ ~6 R
# `0 o$ w4 G, m# v5 `+ M+ C, X& [2 I0 k7 O8 d
0 J. O+ Q; T2 `* W; u$ J3783 Patient (Pt)-Driven Discontinuation of Tyrosine Kinase Inhibitor
4 b }- g2 d; n; \4 TTheray in Chronic Phase Chronic Myeloid Leukemia (CML) - Single
% l2 g2 [6 J* D. aInstitution Experience2 U6 U9 h, W5 I- U
Program: Oral and Poster Abstracts
0 X- O2 _ t/ L3 l5 }Session: 632. Chronic Myeloid Leukemia - Therapy: Poster III
/ i+ Y# ^6 f5 x
5 T) K- P$ P4 U. m; GMonday, December 10, 2012, 6:00 PM-8:00 PM6 w9 ?2 O# {: V) {7 \: k
: i6 n- T! }9 S
Hall B1-B2, Level 1, Building B (Georgia World Congress Center) U: C% S( T! R
" U9 K! m8 c3 O* J& {% KOhad Benjamini, MD1*, Hagop M. Kantarjian, MD1*, Mary Beth Rios, RN1,: F' `$ Q& R' `6 O' v& ^$ X
Elias Jabbour, MD2*, Susan O'Brien, M.D.1, Preetesh Jain, MD, DM, PhD1*, A, [$ d& V; K- O* j
Stefan Faderl, MD1, Guillermo Garcia-Manero, MD1*, Farhad Ravandi, MD1,+ M" a5 H+ ^; z9 }6 b
Gautam Borthakur, M.D.1, Alfonso Quint醩-Cardama, MD1* and Jorge E.0 o9 a1 Z, r" k: y
Cortes, MD1! n# ^9 s0 N0 Q% v2 p
0 l1 ?# \/ a! z, Y1Department of Leukemia, The University of Texas MD Anderson Cancer
' n1 \1 V* U7 xCenter, Houston, TX2 t) r$ H# I% U6 N6 P, R
2Department of Leukemia, The University of Texas M.D. Anderson Cancer$ x3 D" \ S- X% c" G
Center, Houston, TX1 h/ M7 ]4 Q3 A; O
- T: T- h6 h8 _3 l- wIntroduction: Some recent studies have reported on the outcome of CML
* i- }! k. e) Y0 t4 Lpts who discontinued thyrosin kinase inhibitors (TKI) after achieving
* o6 T' R: Z3 B) J- Hsustained undetectable bcr-abl transcript level. Most patients who stop) d. {3 F' J' j! d9 x+ b+ `
TKI have experienced molecular relapse. Most patients respond after
1 y( r7 W" j! K& I2 c0 gresuming TKIs regaining undetectable bcr-abl transcript levels. These8 c; o8 {2 u/ q, D( o7 N
series have prospectively planned treatment discontinuation and included; q' ~ {; z6 H5 O! T' ?
only pts that have sustained complete molecular response (CMR) for at$ a1 S2 I% R& H3 D( }% {6 t
least 2 yrs. However, in many instances pts may want to discontinue TKIs
* C% o5 l, ?: K* ?1 `: i+ Tnot in CMR. Various reasons may lead patients to discontinue TKI
$ b" h# O% Q" c1 f1 }8 o& ]treatment unexpectedly, among them severe adverse effects, pregnancy or9 u: D9 \1 U: T: D# W0 M
economic constraints. This single institution experience reflects the, v' A5 S; g' l
heterogeneous nature of pt-driven TKI discontinuation.
# x- A# A: Y+ U
8 e1 w' y- M3 C0 z6 h; X6 ^, K# H' NAim: To characterize the outcome and profile of CML pts who chose to$ [2 v6 X* b i! I( D I. @. u' W
discontinue TKI therapy in a single center regardless of their initial
" M7 k5 \: \ O7 v/ r/ L, Vresponse to TKI therapy.
: A3 r' V! r* M$ p$ {' J7 _8 a% x( j% P$ f( R
Methods:We retrospectively analyzed MDACC data on all patients with CML
; I) U; X. p) c, j( s- R2 othat were treated with TKIs in our institution and discontinued therapy.& O) V( c' ]! Q% \4 R- e4 t, b
. K) K& k3 p8 O3 aResults: A total of 26 patients with CML-CP managed at MDACC
. ~5 B+ y) Q1 xdiscontinued TKI between 2003 and 2012. The total median follow up time
: p5 d. T5 Z' q8 ]7 r! Csince diagnosis was more than 120 months (mos) (range, 45 mos to 304$ [5 `5 ]/ V) M- `# w4 z
mos). The median age at diagnosis was 48 yrs (range, 28-73); 15 pts were/ G. t( ?0 s1 A o
female. All pts had been diagnosed and treated in chronic phase.
4 k C2 s/ N$ L- r7 W& vInterferon was initial therapy in 11 pts (42%) and 15 pts received TKI4 T9 V0 @1 W$ G, T# m$ s0 M/ n% }
as initial therapy (4 received imatinib 400mg/day, 10 imatinib
3 m) _0 E8 V4 D' U2 H600-800mg/day, and 1 bosutinib.) Of the 11 pts initially treated with0 O* c: X/ R& x0 o N. O" {
IFN, 7 then received imatinib 400mg and 4 imatinib 800mg upon IFN
8 t k" w$ R1 U3 x6 x6 xfailure. Pts treated frontline with TKI started therapy within a median
2 u% B$ O0 X# } `0 yof 0.8 mos from diagnosis (range 0 to 4) and those with previous
! u8 z" f9 d8 J! q: V4 x, S+ ninterferon (n=11) after a median of 60 mos from diagnosis (31 to 164, G0 D K' e0 v' w' P& v! Q
mos). Before TKI discontinuation 21pts (81%) were receiving their first5 \' E" C1 ?; S3 h K8 P+ j
TKI and 5 (19%) were receiving 2nd (4) or 3rd line (1) TKI. Complete
, R- H1 p% h: M5 N3 jcytogenetic response (CCyR) had been achieved in all 26 pts at a median" I: q/ C# w$ v9 d& }
of 3.5 mos (3-93); Major molecular response (MMR) in all at a median of
) l3 n! o$ D# h1 i1 K6 z6 |9 mos (3-73) and CMR in 17 (65%) at a median of 22 mos (9-120). All8 W7 A7 `& z! w @ P( q
patients discontinued therapy in CML-CP, all in CCyR, of them, 17 (65%)7 G) u1 N B4 m
had undetectable transcripts, 2 (8%) had MR4.5, and 7 (27%) MMR. The
) N4 X# C0 O& _' v# Smedian duration of CMR before TKI cessation was 62 mos, (0- 118). The+ h% t; t% c& Y# G N* @2 f( @7 J
median duration of total TKI therapy was 101 mos (3- 135).2 G9 C. C$ L; a3 O! W7 t* w
8 q+ O1 V2 u! l4 }" c4 R) h" V
Fourteen pts (54%) discontinued TKI due to adverse events, 2 pts4 |& H9 p! Z G3 s: p% q
discontinued to become pregnant, 5 decided to stop after long CMR, and 5$ z1 _4 ?4 [' c0 C; [! S
pts discontinued for financial reasons. After TKI discontinuation
2 Y( y; r# ], U; H( J8 lpatients were followed for a median of 11 mos (5-131). Among pts with& _+ k j; T0 g; d4 @# _+ U
CMR at discontinuation, molecular relapse occurred in 8 (47%) pts at a
+ p& J( g2 y* x- x/ imedian of 4 mos (1-11) from discontinuation with median transcript level& v4 ]% U/ d2 q9 U
at relapse of 0.07 (IS) (range, 0.004-2.17). Six pts with initial INF. E0 o! H( U( G; I/ P9 N5 l `" `6 T6 v
therapy had CMR at time of TKI discontinuation, 50% of them relapsed.+ @, ~+ V, P1 H- w. o0 N3 Z: m/ L% V
Among 7 pts who discontinued therapy in MMR, after a median follow-up. ^. y% s) ?. M" _" C/ h/ M
from discontinuation of 21.6 months (range, 4.6-106), 4 remained at MMR,) G7 ?' C: H3 Q6 K2 D* l2 _
one has minor CyR and one CCyR without retreatment at last follow up. u" S. v4 w0 E7 p; R7 G
after 78 and 105 months from TKI discontinuation, and one transformed to1 ]; H& e( A& C$ |. p
accelerated phase (AP). The 2 pts with MR4.5at discontinuation relapsed2 L" J2 d8 `8 k) G7 }
to MMR. Three pts had a transient molecular recurrence with spontaneous/ L' T$ _" L1 Q f3 l6 m, J$ d
re-gain of CMR. Seven pts with relapse were treated again with TKI, 3
4 q: `) W( O6 l% ~8 i4 e# R. e q) ~with nilotinib, 2 with dasatinib, and one each with imatinib and
7 T G# x1 |) C& gbosutinib (the later in AP). After a median of 13 months on therapy3 ?. p2 i1 A, h* [+ v R5 d
(range 4-52) all patients improved their response, 5 with CMR and 2 MMR; V! e( u9 k' b6 T1 E7 x1 e
(including the pt that had transformed to AP). There were no deaths or
% ]+ p( o3 ^+ q3 D+ Ntransformations to blastic phase of CML. At last follow up 14 (54%) pts
3 [( _$ T! k% N+ H4 mwere in CMR, 5 (19%) in MMR,5 (19%) in CCyR and 1 each in minor CyR and
4 s5 k4 V( r! v1 @. A& }PCyR.# P- q% w9 f6 j% O) @
- \4 B z8 ~; r1 s' sConclusion: Pt-driven TKI discontinuation in CML-CP leads to molecular" G: F4 _1 O1 n. ^( P" {
relapse in nearly half of the pts who discontinue therapy in CMR. Some
. v- J* @, A9 Z! D& h0 l# ^5 O/ Jpts who discontinue in MMR may have sustained MMR. Treatment: z# [' b, l1 U+ ]% `& @3 m
discontinuation should be considered experimental and cannot be( L- m8 x; J \7 r/ D5 R
recommended to pts as a standard approach.# c' Y' p) \5 h3 ^
A( \ B9 R1 B; sDisclosures: Ravandi: BMS: Honoraria, Research Funding. |