ALK G1202R

While first-line treatment options include alectinib, brigatinib, and lorlatinib per National Comprehensive Cancer Network (NCCN) guidelines, therapeutic challenges arise in cases of disease progression. Direct comparison of second and third-generation ALK inhibitors is essential to elucidate their comparative efficacy and adverse event profiles, which could refine current management guidelines. Furthermore, if lorlatinib proves superior in terms of progression-free survival, it may offer the potential to delay or obviate the need for radiation therapy, thus mitigating the risk of neurotoxic adverse events associated with these modalities.

The tight binding of TPX-0131 to residues Arg1202, Met1199 and Arg1120 contribute significantly to overcoming lorlatinib resistance in ALKL1196M/G1202R mutant. These research results are expected to offer insights into the mechanism of TPX-0131 in treating ALKG1202R/L1196M-induced NSCLC resistance and optimizing of ALK inhibitors.

ORNi-PCR followed by ddPCR/real-time PCR enables highly sensitive and accurate detection of ALK mutations by liquid biopsy. Although the clinical data are limited, our results show that these methods are potentially useful for identifying ALK-TKI-resistant NSCLC at the early recurrent phase.

Collectively, resistance of ALK-positive NSCLC cells to crizotinib is induced by G1202R and L1196M mutations through activation of the MDM2/MEK/ERK signalling axis, promoting EMT process and metastasis. These findings suggest that the combination of MDM2 inhibitors and crizotinib could be a potential therapeutic strategy.

A series of rigid ALK PROTACs were developed through conjugation of Ceritinib and thalidomide, orally bioavailable PROTAC 4B (F = 14.22 %) was obtained by overall optimization of molecular properties. Furthermore, 4B significantly inhibited the growth of Karpas 299 xenografts in vivo with TGI of 49.5 % and showed superior anti-proliferative activity against G1202R mutation to Ceritinib (IC50 = 52.82 nM vs IC50 = 109.5 nM). Overall, 4B is expected to be a potential treatment for ALK-driven malignancies.

These preclinical findings are supported by three case studies from an ongoing first-in-human phase I/II trial of NVL-655 which demonstrate preliminary proof-of-concept clinical activity in heavily pretreated patients with ALK fusion-positive non-small cell lung cancer, including in patients with brain metastases and single or compound ALK resistance mutations. Significance: By combining broad activity against single and compound ALK resistance mutations, brain penetrance, and selectivity, NVL-655 addresses key limitations of currently approved ALK inhibitors and has the potential to represent a distinct advancement as a fourth-generation inhibitor for patients with ALK-driven cancers.

Several anaplastic lymphoma kinase (ALK) tyrosine kinase inhibitors (TKIs) have been developed for the treatment of echinoderm microtubule-associated protein-like 4 (EML4)-ALK-rearranged non-small cell lung cancer (NSCLC), with the newer generation agents brigatinib, alectinib and lorlatinib showing prolonged responses. The second ALK resistance mutation detected after a chemotherapy interval, the G1202R, is the most common resistance mutation after second generation ALK TKIs and has been associated with sensitivity to third generation TKIs, such as lorlatinib. This case of a patient with EML4-ALK-rearranged NSCLC shows that sequential treatment with next-generation ALK TKIs, including rechallenge, can induce profound remissions, even in heavily pretreated patients, and that ALK-targeted strategies may be personalized by considering the presence of distinct ALK resistance mutations.

V3 status is also associated with specific patterns of clinically important ALK resistance mutations. These tumor-intrinsic features may inform rational selection and optimization of first-line and consolidative therapy.

Both fluorouracil, leucovorin, and oxaliplatin (FOLFOX) and bevacizumab combined with 5-fluorouracil, l-leucovorin, and irinotecan (FOLFIRI) proved ineffective against the disease...The patient was initially treated with ensartinib monotherapy for 9 months, then with ensartinib combined with local radiotherapy and fruquintinib for another 4 months for isolated hilar hepatic lymph node metastasis. The patient experienced disease progression with an acquired ALK G1202R resistance mutation that responded well to lorlatinib...However, the patient responded remarkably well to alectinib. Our report emphasizes the importance of gene detection in the treatment of malignant tumors, and the significance of ALK mutations in CRC.

In cases of ALK-dependent resistance mutations, lorlatinib could be the first choice as it exhibits the broadest coverage of mutations that lead to resistance against second-generation ALK - TKIs, such as G1202R, and L1196M. In cases of no resistance mutations, atezolizumab, bevacizumab and platinum-based chemotherapy could be the alternative treatment option.

Our findings suggest that real-time quantitative monitoring of ALK resistance mutations during the response period could provide a time course of changes while acquiring resistance mutations. This information would be beneficial for designing an appropriate treatment strategy.

Legal entity responsible for the study Fondazione Policlinico Universitario A Gemelli – IRCCS. In post-lorlatinib NGS-assay, 2 pts had ALK-compound mutations, while 4 pts had newly off-target alterations (CDKN2A/B CDKN2B loss, NF1 deletion, DNMT3A/ARID1A/CHECK2 M+). Conclusions Implementation of longitudinal genomic assessment is required in order to provide an extensive overview of resistance mechanisms and clinical outcomes according to current ALK-inhibitors treatment sequences.

Gene co-occurrence survival analysis showed that mPFS of pts harboring FAT3/FAT4 mutations were significantly shorter than those without FAT3/FAT4 mutations (8.9 mo vs 16.5 mo, p=0.012). Conclusions Clinical utility of ctDNA was demonstrated, not only at baseline by identifying fusion types and subgroups of ALK+ NSCLC pts that may benefit more from SAF-189s, but also at progression by tracking ALK-resistant mutations.

In Cohort 1 (n=21), 15 (71%) pts had progressed on alectinib, 5 (24%) on ceritinib and 1 (5%) on ensartinib. In Cohort 2 (n=18), pts had progressed on crizotinib followed by alectinib (n=9, 50%), ceritinib (n=4, 22%) or brigatinib (n=3, 17%); 2 (11%) pts progressed on crizotinib, then ceritinib followed by alectinib...Of 5 pts with ALK resistance mutations (I1171N, V1180L, L1196M, G1202R, and E1210K) who subsequently received lorlatinib, repeat ctDNA NGS after 2 months demonstrated clearance of ALK resistance mutation(s) in 4/5 (80%) pts (i.e. undetectable on repeat testing)... Resistance mechanisms to ALK inhibitors are heterogenous, including both ALK dependent and independent pathways. DDR and cell cycle gene alterations were commonly detected and may represent previously unreported acquired resistance alterations. Comprehensive ctDNA NGS analysis at progression may help detect novel resistance alterations in patients on ALK inhibitors.

The dynamic changes of genomic characteristics during lorlatinib treatment revealed the mutation landscape of Chinese patients with NSCLC after ALK-TKI resistance, indicated that the resistance profile of lorlatinib were heterogeneous, which laid the foundation for subsequent treatment to overcome lorlatinib resistance.

However, resistance to ALK inhibitors can occur via point-mutations within the kinase domain of the EML4-ALK fusion, e.g. G1202R, reducing inhibitor effectiveness. Here, we discuss the biology of EML4-ALK variants, their impact on treatment response, ALK-TKI drug resistance mechanisms, and potential combination therapies.

19 novel imidazo[1,2-b]pyridazine macrocyclic derivatives were designed, synthesized, and tested for their biological activities in an effort to develop ALK inhibitors that would overcome second-generation ALK-TKIs, particularly the G1202R mutation and the lorlatinib-resistant L1196M/G1202R double mutations...This was equally effective to the reference drug Repotrectinib (IC = 40, 164, and 208 nM). The kinase selectivity profile, liver microsome stability test and in vivo pharmacokinetic properties in SD rats of compound O-10 were further evaluated. O-10 was regarded as an effective ALK inhibitor for the treatment of mutations overall.

Background: TGRX-326, a deuterated derivative of lorlatinib (LOR), is a potent 3rd generation ALK and ROS1 dual TKI with high potency against multiple ALK-resistant mutations...In D-ESCAL and D-EXP, ALK+ pts prior failed on 2nd gen ALK-TKIs or ROS1+ pts resistant to crizotinib (CRZ) were enrolled; in C-EXP, ALK+ pts progression after CRZ (C-EXP-A1),progression after ≥1 2nd gen TKIs (C-EXP A2), ROS1+progression after CRZ (C-EXP-B) and pts with ALK TKI naïve (C-EXP-C) were enrolled... TGRX-326 was well tolerated in pts with advanced ALK+NSCLC and showed promising clinical antitumor activity irrespectively of ALK+ resistance to CRZ and 2nd gen TKIs, especially among those with brain metastases. Impressive activity was seen in ALK TKI naïve NSCLC. TGRX-326 demonstrated antitumor activity against multiple ALK mutations including G1202R.

Second- (ceritinib, alectinib, brigatinib, and ensartinib) and third-generation (lorlatinib) ALK TKIs have higher intracranial responses than crizotinib but are still limited by emergence of resistance mutations, most commonly G1202R-containing single and compound mutations. Patient-derived models are widely viewed as among the most disease-relevant models for evaluating new therapies and drug resistance. Using a xenograft model derived from an alectinib-relapsed patient, we showed that NVL-655 had high intracranial activity against brain tumors bearing the ALK G1202R mutation that confers resistance to multiple ALK TKIs. NVL-655 is being evaluated in a Phase 1/2 clinical trial for patients with advanced NSCLC and other solid tumors harboring ALK rearrangement or activating ALK mutation (ALKOVE-1): NCT05384626.

Osimertinib-resistant YU-1097 harboring EGFR resistance mutation (E19del/T790M/C797S) revealed sensitivity to BLU-945 (IC50, 108nM), a novel fourth-generation EGFR-TKI. A similar inhibition of cell viability was observed with repotrectinib (IC50, 21nM), a next-generation ROS1-TKI and lorlatinib (IC50, 9nM) in YU-1078 harboring CD74-ROS1, whereas more robust tumor regression was seen with repotrectinib in YU1078-derived xenograft model. Amivantamab, a EGFR-MET bispecific antibody, showed a robust activity in YU-1163 and YUO-036 in vitro and in vivo. PDC/PDO models can be utilized for evaluating activity of novel agents and will accelerate novel drug development in NSCLC.

Longitudinal analysis of circulating tumor DNA will be performed, including ALK mutation profiling and other relevant biomarkers. The phase I portion of the study is ongoing.

Conclusion This study shows the prolonged efficiency of crizotinib in selected patients. Additional results will be presented during the congress.

Despite early progression within 3 mo under crizotinib, a durable response was achieved with alectinib...Another rebiopsy revealed ALK:p.L1196M, but the tumor did not respond to brigatinib or carboplatin/pemetrexed, before stabilization under lorlatinib...Lorlatinib retained efficacy in the heavily pretreated setting, while its upfront use could possibly have prevented the stepwise emergence of compound ALK mutations. Furthermore, the disease course was more aggressive and OS shorter compared to the V2/TP53wt ALK+ lung adenocarcinoma, while crizotinib, ceritinib and brigatinib did not confer the benefit expected according to NGS results, which also underline the need for more potent drugs against ALK in the high-risk setting of neuroendocrine histology.

He was started on Alectinib 600mg twice daily with zoledronic acid from Aug 2017. Molecular testing and looking for ALK resistance mutation helps to choose Lorlatinib, the only sensitive TKI which targets (G1202R). This is an evolving precision based therapy, improves outcome in lung cancer.

In ALTA-2, brigatinib demonstrated limited activity in patients with ALK+ NSCLC post-ceritinib or post-alectinib therapy. Median PFS was longer with brigatinib in patients without baseline detectable plasma ALK fusion.

Five tyrosine kinase inhibitors (TKIs) have been approved for treatment of ALK-positive non-small cell lung cancer (NSCLC), including first- (crizotinib), second- (ceritinib, alectinib, and brigatinib), and third- (lorlatinib) generation therapies. NVL-655 showed activity in diverse patient-derived models of ALK-positive cancers, including ones that exhibited clinical resistance to prior-generation ALK TKIs. The broad preclinical activity of NVL-655 suggests potential utility as a best-in-class therapy for ALK-positive cancer patients.

Of these, 52 received first-line alectinib treatment (1L) and 56 received alectinib after crizotinib resistance (2L). Also, NF2-mutant patients only had a median PFS of 4 months, significantly poorer than those without (HR 11.1, 95CI 2.17-50; p<0.001). Conclusions By analyzing different mutational profiles of ALK-rearranged patients after alectinib treatment, we proposed MET and NF2 as putative mechanisms that conferred resistance to early resistance of first-line alectinib, which shone light on future tailored treatment for ALK-positive NSCLCs.

Results Of the 133 pts who progressed on alectinib, with or without prior crizotinib or chemotherapy, 131 had evaluable baseline plasma data. The presence of secondary ALK mutations at baseline was associated with a similar ORR (34.5%) and median DoR (5.6 months) and shorter median PFS (3.7 months), with response/clinical benefit observed in pts with G1202R, L1196M, and I1171N ALK secondary mutations. Table: 1009P Brigatinib efficacy parameters a according to baseline ALK mutation status conclusions Brigatinib showed clinically meaningful activity in pts with alectinib-resistant ALK+ NSCLC with or without a detectable ALK fusion and/or secondary mutations.

Structural analysis revealed increased potency against compound mutations through improved inhibition of either G1202R or I1171N/S/T mutant kinases. Overall, we propose a classification of heterogenous ALK compound mutations enabling the development of distinct therapeutic strategies for precision targeting following sequential tyrosine kinase inhibitors.

Patients with ALK+ NSCLC experienced more unfavorable prognosis and were more prone to develop CNS progression compared with those with ROS-1+ NSCLC following the treatment of crizotinib.ROS-1ALKP valueExtrathoracic metastases62.5%(25/40)77.8%(35/45)0.155CNS metastases20%(8/40)26.7%(12/45)0.61Multiple CNS metastases62.5%(5/8)50%(6/12)0.67Measurable CNS lesions37.5%(3/8)50%(6/12)0.67Liver metastases7.5%(3/40)17.8%(8/45)0.204Bone metastases27.5%(11/40)42.2%(19/45)0.117≥3 distant organs involved25%(10/40)31.1%(14/45)0.632

Crizotinib, ceritinib, alectinib, brigatinib, and lorlatinib are approved tyrosine kinase inhibitors (TKIs) for ALK-positive NSCLC, but durability of response is partly limited by ALK resistance mutations...Ascites mononuclear cells were isolated by Ficoll centrifugation and cultured in media (DMEM F12 Glutamax, 10% antibiotics/antimycotics, 10% FBS, hydrocortisone, adenine, RockInhibitor, and 1/10 cholera toxin)... NVL-655 has demonstrated activity in many preclinical models bearing ALK compound mutations, including the MR448re (EML4-ALK v3 G1202R/T1151M) model. The potent preclinical activity of NVL-655 suggests potential clinical utility for ALK-positive patients, including those with resistant compound mutations. The MR448re PDC and xenograft are valuable additions to the ALK therapeutic research landscape where there is limited availability of patient-derived models with lorlatinib-resistant ALK compound mutations.

In 20 eligible patients (median [m]age 63 years [range, 40-89], females 75%, adenocarcinoma 100%, failure of alectinib 90%, FoundationOne Liquid CDx 80%), CGP has altered NLST recommendation in 30% of cases (Figure 2)... CGP has a significant impact on the decision-making process in ALK-rearranged aNSCLC following progression on 2nd/3rd-generation ALK TKIs.

In 20 eligible patients (median [m]age 63 years [range, 40-89], females 75%, adenocarcinoma 100%, failure of alectinib 90%, FoundationOne Liquid CDx 80%), CGP has altered NLST recommendation in 30% of cases...mOS was 13.2 months (95% CI, 2.9-NR) and 13.0 months (95% CI, 6.0-NR) in groups 1 and 2, respectively (p-0.86). CGP has a significant impact on the decision-making process in ALK-rearranged aNSCLC following progression on 2/3-generation ALK TKIs.

Another pt with the G1202R mutation following alectinib treatment had tumor shrinkage of 27.9%. APG-2449 has a favorable safety and PK profile and was well tolerated in 84 subjects. Preliminary efficacy was observed in pts whose disease was resistant to second-generation TKIs, especially among those with brain metastases, and in TKI-naïve pts. Biomarker data indicated potential target engagement on FAK and immunomodulatory effects of APG-2449.

No abstract available

cfDNA-NGS facilitates detection of ALK fusions and resistance mutations, assessment of prognosis, and monitoring dynamic changes of genomic alterations in ALK+ NSCLC treated with ALK-TKI.

Estimated CNS concentrations exceeded the derived CNS C in all patients for wild-type ALK and the ALK L1196M mutation and in 35.8% of patients for the ALK G1202R mutation. Projected lorlatinib CNS concentrations were consistent with the high intracranial response rates reported in clinical trials and provide further evidence of the potent CNS penetration of lorlatinib.

Furthermore, the combination of ALK and STAT3 inhibitors restored the sensitivity of EML4-ALK G1202R mutant cells to ceritinib. In conclusion, these data indicate that the EML4-ALK G1202R mutation mediates the EMT phenotype by activating the STAT3/Slug signaling pathway, resulting in resistance to ceritinib, and that the combination of STAT3 and ALK inhibitors may overcome ALK mutation-driven drug resistance in the clinic.

Sequential postprogression plasma profiling revealed that increased lines of ALK inhibitors can accelerate the accumulation of ALK resistance mutations and may lead to treatment-refractory compound ALK mutations. The selection for optimal first-line TKI is very important to achieve a more efficacious long-term strategy and prevent the emergence of on-target resistance, which may provide guidance for clinical decision making.