CLL (BSH 2022, BSH 2018)

CD5+, CD23+, Surface Ig weak+, Strong CD43+, CD200+

CD79b -, FMC7-

CLL Haemlysis.jpg

 Intro

 

Incidence 4.2 per 100,000 per year in UK

Median age of presentation 72

Men > Women

Caucasian > other ethnic groups

>80% incidental diagnosis

 

Diagnosis

 

>5 x10e9/l circulating clonal B cells persisting for >3 months and of characteristic immunophenotype.

 

CLL Score (now outdated for many centres, as different CD markers often used)

  • Surface Ig weak, CD5+, CD23+, CD79b-, FMC7-

  • One point for each

  • 92% of CLL scores 4 or 5

 

Prolymphocytes:

  • >15% prolymphocytes = Prolymphocytic progression of CLL (as of 2022, this replaces B-PLL)

 

DDx for CD5+ LPD with a low score = atypical CLL, mantle cell, marginal zone

 

cMBL = clinical CD5+ monoclonal B cell lymphocytosis

  • MBL detectable on a routine FBC but <5 x109/l monoclonal cells

  • WHO 2016 splits <0.5x109/l (no concern) from 0.5-5 x109/l (annual FBC monitoring)

 

Staging

 

BINET

  • A: <3 lymphoid areas

  • B: 3 or more lymphoid areas

  • C: Hb <100 or Plt <100

  • (Five lymphoid areas are: uni or bilat. cervical, axillary, inguinal, hepatomeg, splenomeg)

RAI

  • 0: Low risk: Lymphocytosis only

  • I: Intermediate: Lymphadenopathy

  • II: Intermediate: Hepatomeg or splenomeg + lymphocytosis

  • III/IV: High risk: Hb <110 or Plt <100

 

Investigations

 

Asymptomatic Stage A patients

  • FBC, reticulocyte, DAT, biochemistry, immunoglobulins, Hep B/C, HIV

  • Flow cytometry

  • TP53 deletion (FISH)

  • Lymph node biopsy only if diagnostic uncertainty

  • CT not required at diagnosis (perform later pre-treatment)

Diagnosing transformation

  • 5-15% of CLL transforms to DLBCL-like or HL-like

  • May be localized, biopsy the suspicious site

  • PET-CT may help identify best biopsy site.

Assessing prognosis

  • Binet / Rai systems predict outcome in advanced stage patients, but poor for early stage

  • Other factors:

    • Age, Gender, PS, co-morbidities

    • Marrow failure, immunodeficiency, autoimmunity, biomarkers

    • Type of treatment, Response, Toxicity, MRD status

  • Prognostic data should not influence timing of first treatment

  • Biomarkers include IGHV gene analysis, B2M, CD38 positivity

TP53

  • TP53 loss (del 17p13.1) occurs in 5-10% of patients at diagnosis, 30% in fludarabine refractory patients

  • TP53 mutation occurs in an additional 5% at diagnosis, 12% of refractory patients

  • Both TP53 loss and mutation indicate high risk disease, associated with lower response rates and short PFS when treated with chemoimmunotherapy (e.g. FCR or R-Benda).

IGHV

  • IGHV gene mutations confer a better prognosis

  • ?functional cure in 50% treated with FCR, and excellent remissions with O-Venetoclax

  • ‘IGHV unmutated’ is associated with a poorer prognosis.

Management

 

Indications to treat:

  • Lymphocyte doubling time <6 months (provided starting Lymph count >30)

  • Lymphocyte count increased >50% in 2 months

  • Progressive marrow failure

  • Massive (>6cm below costal margin) splenomegaly

  • Massive (>10cm) lymph nodes

  • Autoimmune anaemia / thrombocytopenia not controlled by standard therapy

  • Constitutional symptoms

    • Wt loss >10% in 6 months, fatigue (PS 2 or worse), Fever >38 for 2 wks, night sweats for >1 month.

(NOT indications to treat - High lymphocyte count (in absence of rapid doubling time), hyperviscosity and hypogammaglobulinaemia (in absence of recurrent infection))

Choosing therapy

  • No single choice, patient-by-patient

  • Age, co-morbidities, creatinine clearance, PS, susceptibility to infection

  • Important to achieve maximal response

    • Achieving MRD negative remission is an independent marker for OS and PFS

Defining response

  • IWCLL criteria for CR, PR and progressive disease

  • Relapse = disease progression at least 6 months after achieving CR / PR

  • Refractory = treatment failure or disease progression less than 6 months after CR/PR

CLL response.jpeg

 

Treatment not required for Early / Stage A Disease

  • 6 monthly review in first year to assess rate of progress

  • Then annually if no concern, GP or hospital

  • Address patient and family concerns around leukaemia diagnosis and implications

 

Treatment Principles

  • Irradiated blood products

    • For life: purine analogies, bendamustine, campath

    • 3 months post-conditioning for autograft

  • MDT approach

  • Offer clinical trial

 

Front-line Treament Options (Subject to frequent change!)

Targeted therapies +/- Immunotherapy have replaced traditional cytotoxic chemotherapy and have softened the distinctions between fit / unfit and TP53/noTP53. However some NICE approvals are still based on these groups.

UK Patients without TP53 abnormality

UK Patients with 17p / TP53 disruption (deletions and/or mutations)

Other approved options, less commonly used first line in UK now:

  • R-Idelalisib - acceptable alternative if specific issues prevent others (e.g. cardiac disease, warfarin use)

  • Obinutuzumab-Chlorambucil (CLL11 - PFS and TTNT benefit vs R-Chlormabucil)

  • FCR (CLL10)

  • R-Bendamustine

Maintenance in CLL?

  • No. Anti-CD20 antibodies and lenalidomide have been trialed - increase PFS but no effect on OS seen, and need to weigh the long-term toxicity

Relapse/Refractory Options (Subject to frequent change!)

Options (Guideline has recommendations on sequencing):

When to consider allogeneic stem cell transplant?

  • Fit patients who have failed at least 2 of :chemoimmunotherapy, BTKi, BCL2i

  • Fit patients with Richter transformation

 

Supportive Care

Anti-microbial prophylaxis

  • PCP prophylaxis for at least first 12 months of BTKi

  • Aciclovir prophylaxis with intensive treatment or low CD4 counts

  • Azoles avoided in combination with BTKi and BCL2i due to interactions

Hypogammagloublinaemia

  • Prophylactic antibiotics for recurrent infections

  • Consider immunoglobulin replacement 3-4 weekly if low IgG (<4g/l) and recurrent infection. Discontinue after 1 year if not reduction in rates of infection.

Vaccination

  • Annual flu vaccination

  • Pneumococcal vaccination - Prevnar13 followed by Pneumovax23 two months later

  • Shingles - non-live vaccine now available (Shingrix)

Drugs: A few notes

Covalent Bruton Tyrosine Kinase inhibitors (BTKi) (Also see here)

  • Ibrutinib, Alcalabrutinib, Zanubrutinib

  • SE: acquired platelet function defect, hold for 5-7 days before interventional procedures / surgery

  • SE: Petechial rash, easy bruising & arthralgia usually improve with time

  • SE: Hypertension, AF & VT (including sudden cardiac death)

  • SE: With alcalabrutinib also look for headache, gastritis. But probabaly less cardiac side effects than ibrutinib (N.B. new tablet formulation of acala no longer has an issue with concurrent use of PPI’s)

  • Avoid CYP3A4 inhibitors - warfarin, fish oils, Vitamin E, St Johns Wort

  • Grapefruit and Seville oranges must be avoided

Non-Covalent BTKi

  • e.g. Pirtobrutinib

  • Alternative, reversible mechanism of binding BTK compared to covalent inhibitors (review paper 2021)

  • —> Can still be effective after resistance has developed to covalent BTKi’s

  • Typical BTKi side effects (bruising, rash, arthralgai, AF) may be less common and less severe.

BCL2 inhibtior - Venetoclax

  • MOA: Inhibitor of BCL2. BCL2 is a anti-apoptotic protein that is overexpressed in cells of many haematological malignancies. Apoptosis is reduced in these cells because BCL2 sequesters the pro-apoptotic protein BAX. —> Inihibiting BCL2 releases BAX which leads to cell death.

  • Significant risk of tumour lysis (—> dose escalated slowly over course of first cycle)

  • CLL14 trial

Ibrutinib + Venetoclax

  • Proposed to be synergistic when given in combination

  • Ibrutinib drives CLL out of lymph nodes, into peripheral blood where more sensitive to venetoclax

  • BTK inhibition makes CLL cells more dependent on BCL2 —> increased sensitivity to venetoclax

  • A 3 month lead in with ibrutinib reduces the risk of tumour lysis syndrome associated with venetoclax

PI3 Kinase Inhibitors - Idelasilib

  • May trigger life-threatening pneumonitis or colitis

  • Monitor liver function

  • Monitor CMV PCR’s

  • Use PCP prophylaxis

A Few Trial notes

CLL13 2023

  • Phase 3, First line CLL for fit patients without TP53 disruption

  • 926 patiens. 1:1:1:1 randomisation:

    • FCRx6 or R-Benda x6

    • R-Venetoclax x12

    • O-Venetoclax x12

    • Venetolax-O-Ibrutinib x12

  • At 15 months, uMRD V-O-I (92%) & O-V (86%) vs R-V (57%) & Chemo (53%)

  • 3-yr PFS was V-O-I (90.5%) & O-V (87.7%) vs (80%) & Chemo (75.5%)

  • Grade 3/4 infection was V-O-I (21%) vs O-V (13%)

ALPINE 2023

  • Phase 3, R/R CLL, Ibrutinib vs Zanubritinib

  • 2yr PFS: 78% zanubrutinib, 65% ibrutinib

  • Rates of drug discontinuation + cardiac events lower with zanubrutinib vs ibrutinib

GLOW 2022

  • Phase 3, First line CLL. Ibrutinib+Venetoclax vs O-Chlormabucil

  • 211 patient, >65 yo (or high frailty score (CIRS) or CrCl <70ml/min)

  • Excluded del17p and TP53 mutation patients.

  • undetectable MRD (uMRD) I+V 55% in BM

  • 2-yr I+V OS 90%, PFS 84%

SEQUOIA 2022

  • Phase 3, First line CLL. Zanubrutinib vs R-Benda except all 17p del got Zanu (arm C)

  • 590 patients, >65yo or <65 with co-morbidity

  • At 2 yrs, median PFS not reached for either arm but superior for zanubrutinib

  • 50% neutropenia with zanubrutinib

CAPTIVATE 2022

  • Phase 2, First line CLL. 15 months Ibrutinib + 12 months Venetoclax

  • 160 patients, <70 yo only in trial. 92% completed full treatment.

  • CR 55%. For those in CR, undetectable MRD (uMRD) was 90% in PB and 72% in BM.

  • 2-yr OS 98%, PFS 95%

ELEVATE-TN 2020

  • Phase 3, First Line CLL. O-Acala vs Acala va O-Chlorambucil

  • 535 patients, >65 yo

  • 2yr PFS 93% O-A, 87% A, 47% O-C

  • 5 yr f/up: Median OS not yet reached for any arm. Est. 60 month OS 90% A-O, 84% A, 82% O-C

NEJM 2019

  • Phase 2, First line CLL. Up to 24 cycles of ibrutinib + venetoclax

  • 80 high risk patients (del17p, TP53 mutation, del11q, unmutated IGHV or Age >65)

  • CR 88%. Undetectable MRD (uMRD) was 61% in BM

  • Only 3 patients completed 24 cycles of treatment.

CLL14 2019

  • 12 months Venetoclax + 6x Obinutuzumab vs. 12 months Chlorambucil + 6x Obinutuzumab

  • 432 patients

  • O-Venetoclax showed higher rates of complete response, MRD negativity and longer PFS

  • Follow-up off treatment confirmed longer PFS (median PFS not reached in O-V, 35 months for O-C)

MURANO 2018

  • Phase 3, R/R CLL. R-Venetoclax vs R-Benda

  • 389 patients

  • 2-yr PFS 84.9% R-Ven vs 36.3% R-Benda

COMPLEMENT-1 2015

  • Chlorambucil-Ofatunumab vs Chlormabucil alone

  • Combo better PFS but no difference in OS

  • Hard to compare to CLL11 as different dose of chlorambucil used

CLL11 2014

  • Chlorambucil-Obinutuzumab vs Chlorambucil-Rituximab vs Chlormabucil alone

  • Chlorambucil-Obinutuzumab had superior PFS and TTNT

  • Infusion reactions more common with obinutuzumab

CLL10 2013

  • FCR x6 vs R-Benda x6

  • FCR superior for ORR, MRD-neg remissions, length of first remission in young, fit patients

  • FCR arm had more serious adverse events

  • Overall survival similar for both arms