Although imatinib, a BCR-ABL tyrosine kinase inhibitor, is used to treat acute Philadelphia chromosome-positive (Ph ؉ ) leukemia, it does not prevent central nervous system (CNS) relapses resulting from poor drug penetration through the blood-brain barrier. Imatinib and dasatinib (a dual-specific SRC/BCR-ABL kinase inhibitor) were compared in a preclinical mouse model of intracranial Ph ؉ leukemia. Clinical dasatinib treatment in patients with CNS Ph ؉ leukemia was assessed. In preclinical studies, dasatinib increased survival, whereas imatinib failed to inhibit intracranial tumor growth. Stabilization and regression of CNS disease were achieved with continued dasatinib administration. The drug also demonstrated substantial activity in 11 adult and pediatric patients with CNS Ph ؉ leukemia. Eleven evaluable patients had clinically significant, long-lasting responses, which were complete in 7 patients. In 3 additional patients, isolated CNS relapse occurred during dasatinib therapy; and in 2 of them, it was caused by expansion of a BCR-ABL-mutated dasatinibresistant clone, implying selection pressure exerted by the compound in the CNS. Dasatinib has promising therapeutic potential in managing intracranial leukemic disease and substantial clinical activity in patients who experience CNS relapse while on imatinib therapy. This study is registered at ClinicalTrials. gov as CA180006 (#NCT00108719) and

The BCL2 inhibitor venetoclax has revolutionized the treatment of acute myeloid leukemia (AML) patients not benefitting from intensive chemotherapy. Nevertheless, treatment failure remains a challenge, and predictive markers are needed, particularly for relapsed or refractory (R/R) AML. Ex vivo drug sensitivity testing may correlate with outcomes, but its prospective predictive value remains unexplored. Here we report the results of the first stage of the prospective Phase 2 VenEx trial evaluating the utility and predictiveness of venetoclax sensitivity testing using different cell culture conditions and cell viability assays in patients receiving venetoclax-azacitidine (NCT04267081). Participants with de novo AML ineligible for intensive chemotherapy, R/R AML, or secondary AML were included. The primary endpoint was the treatment response in ex vivo sensitive participants and the key secondary endpoints were the correlation of sensitivity with responses and survival. Venetoclax sensitivity testing was successful in 38/39 participants. Experimental conditions significantly influenced predictive accuracy. Blast-specific venetoclax sensitivity measured in conditioned medium most accurately correlated with treatment outcomes; 88% of sensitive participants achieved treatment response. Median survival was significantly longer for ex vivo sensitive participants (14. 6 months for s ensitive, 3. 5 for insensitive, p < 0 . 001). T his analysis illustrates the feasibility of integrating drug-response profiling into clinical practice and demonstrates excellent predictivity.

Long-term engraftment and outcome after ASCT seem to be comparable in NHL patients receiving plerixafor compared to chemomobilized patients. These observations support the use of plerixafor in patients who mobilize poorly.

There is no consensus on treatment strategies for elderly patients with mantle cell lymphoma (MCL). In this prospective phase II study we investigated whether the poor outcome could be improved, with reasonable toxicity, by prolonging the immunochemotherapy. Ten cycles of alternating cyclophosphamide, doxorubicin, vincristine and prednisolone (CHOP)/cytarabine (AraC) with eight doses of rituximab (R) were given as induction. The potential synergism of intermediate-dose AraC and fludarabine was tested in cycles 6-8. Induction was followed by bimonthly rituximab maintenance for 2 years. The median age of the 60 included patients was 74 years, and the Mantle Cell Lymphoma International Prognostic Index (MIPI) was intermediate or high risk in 98% of the patients. The overall response rate was 95% (complete response/complete response unconfirmed 87%). The response of 11 patients improved with cycles 6-8 (R-fludarabine-AraC). Progression-free survival was 70% and overall survival 72% at 4 years, respectively. Treatment related mortality was 2%. Severe infections were rare, with only one grade 4 infection. More dose reductions were needed during fludarabine-containing courses as compared to R-AraC. In 20 patients a transient grade 4 neutropenia without severe infections was recorded during maintenance. In conclusion, elderly patients with MCL can be treated relatively intensively with acceptable toxicity.

Loss of heterozygosity (LOH) has been reported to cause false human leukocyte antigen (HLA) homozygous typing results in pre-transplant patients suffering from haematological malignancies, who in fact are HLA heterozygous. This poses a challenge for histocompatibility testing, as a stem cell graft from a genuinely HLA homozygous donor to a mistyped patient may lead to acute life-threatening graft-vs-host disease. LOH in the HLA region on chromosome 6 is known to be quite common in solid tumours, helping malignant cells to escape T-cell surveillance, but the incidence in haematological malignancies is less well known and the estimates vary. Here we report LOH in the HLA region of five patients with haematological malignancy. We found considerable differences in sensitivity between the three different HLA typing methods used in our laboratory: SSP was clearly the most sensitive method for detecting the lost haplotype, followed by rSSO, while SBT was the least sensitive technique. A subsequent, retrospective genotyping of 65 HLA homozygous haematological patients by SSP method showed no mistyped LOH cases in our laboratory in the past 10 years. The frequency of HLA homozygosity was found to be similar between haematological patients and control groups. It is important for an HLA laboratory to be aware of the differences in various HLA typing techniques' sensitivity for detecting an under-represented haplotype between HLA typing techniques when genotyping patients with haematological diseases. It is advisable for HLA laboratories to have at least two different methods with different sensitivities in their repertoire to be able to retype samples when a false homozygous result is suspected.