A 62-year-old woman with a 6-year history of chronic lymphocytic leukemia (CLL) presents with progressive lymphadenopathy and anemia (Hb 8.5 g/dL). Flow cytometry confirms CD5+, CD19+, CD23+ B-cell CLL. She is FISH-negative for del(17p) and TP53 mutation. What is the preferred first-line treatment for symptomatic CLL?

Question

Accepted Answer

B. Venetoclax + obinutuzumab. ## First-Line Treatment of Symptomatic CLL (Fit Patient, del(17p)-Negative)

**Key Point:** Venetoclax (BCL-2 inhibitor) combined with obinutuzumab (anti-CD20 monoclonal antibody) is the current standard first-line regimen for fit patients with symptomatic CLL, regardless of del(17p) status, based on the CLL14 trial.

### Rationale for Venetoclax + Obinutuzumab

**High-Yield:** The CLL14 trial (2019) demonstrated that venetoclax + obinutuzumab achieves superior progression-free survival (PFS) and minimal residual disease (MRD) negativity compared to chlorambucil + obinutuzumab, even in del(17p)-negative disease.

### Treatment Paradigm Shift

| Regimen | Mechanism | PFS | MRD Negativity | Fit Status | Current Role |
|---------|-----------|-----|----------------|-----------|---------------|
| **Venetoclax + Obinutuzumab** | BCL-2 inhibitor + anti-CD20 | 70–80% at 3 yr | 60–70% | Fit | **First-line (all risk groups)** |
| Ibrutinib | BTK inhibitor | 60–70% at 3 yr | 20–30% | Fit/unfit | Alternative first-line |
| FCR | Chemoimmunotherapy | 50–60% at 5 yr | 40–50% | Fit only | Rarely used (toxicity in elderly) |
| Chlorambucil + Obinutuzumab | Alkylator + anti-CD20 | 40–50% at 3 yr | 20–30% | Unfit | Unfit/elderly patients |

**Clinical Pearl:** Venetoclax requires ramp-up dosing (5 mg → 400 mg over 5 weeks) to minimize tumor lysis syndrome risk; prophylaxis with allopurinol/febuxostat and hydration is mandatory.

**Warning:** FCR, though historically landmark, is now avoided in fit patients due to cumulative myelotoxicity and secondary malignancy risk; reserved only for highly selected young patients with favorable biology.

### Monitoring
- Assess MRD by flow cytometry at end of treatment
- MRD-negative status predicts superior long-term outcomes
- Venetoclax is typically given for 12 months with obinutuzumab induction (6 cycles)

**Mnemonic:** **VEnetoclax + OBinutuzumab = VO** is the modern first-line CLL regimen.

Answer

A. Chlorambucil monotherapy

Answer

C. Fludarabine + cyclophosphamide + rituximab (FCR)

Answer

D. Ibrutinib monotherapy

Explanation

First-Line Treatment of Symptomatic CLL (Fit Patient, del(17p)-Negative)

Rationale for Venetoclax + Obinutuzumab

Treatment Paradigm Shift

Monitoring

Practice similar questions

Join our NEET PG community

Regimen	Mechanism	PFS	MRD Negativity	Fit Status	Current Role
Venetoclax + Obinutuzumab	BCL-2 inhibitor + anti-CD20	70–80% at 3 yr	60–70%	Fit	First-line (all risk groups)
Ibrutinib	BTK inhibitor	60–70% at 3 yr	20–30%	Fit/unfit	Alternative first-line
FCR	Chemoimmunotherapy	50–60% at 5 yr	40–50%	Fit only	Rarely used (toxicity in elderly)
Chlorambucil + Obinutuzumab	Alkylator + anti-CD20	40–50% at 3 yr	20–30%	Unfit	Unfit/elderly patients