XNCR · Xencor

The thesis

Xencor's shares hold a modest edge over the S&P 500 because XmAb819 showed a 45.5% confirmed response rate in advanced clear cell kidney cancer, and the company says its cash funds operations into 2029. Two events in the first half of 2027 decide the case: results from at least 20 evaluable patients at the 400 mcg/kg dose, and the FDA's view on accelerated approval.

Much of the kidney-cancer data is now in the price. The shares closed at $38.13 on 12 November 2026, up 63.4% over three months from $23.34 on 14 August 2026. The day before, they closed at $39.97, the highest close of the past year. Canaccord Genuity kept its Buy rating and $40 target on 10 November 2026, so the shares trade just under that target.

Two insiders sold into the rise, per SEC Form 4 filings dated 12 November 2026. Director Richard Ranieri exercised options on 75,755 shares and sold 81,252 shares at an average $39.25 on 10 November 2026. Chief financial officer Bart Jan Cornelissen sold 10,100 shares at $39.82 on 11 November 2026.

The rating is Medium because the clinical and cash facts still favor the company. The main dated test of XmAb819 falls after the three-month window. Until then, the shares depend on the year-end autoimmune readouts, partner news and the momentum built since the 25 October 2026 data.

Bullish and bearish views on Xencor, Inc.

The bull case on Xencor, Inc. (XNCR), in brief: response rate beat the analyst bar. The bear case: the top-dose sample is 11 patients.

Bull case

• Response rate beat the analyst bar. On 25 October 2026 Xencor reported a 45.5% confirmed response rate at 400 mcg/kg (5 of 11 patients), against a 25% bar set by Truist. The rate was 44% at 200 mcg/kg (25 patients) and 30% at 100 mcg/kg (30 patients).
• Early durability looks favorable. At 400 mcg/kg, median progression-free survival had not been reached in the 25 October 2026 data. The six-month Kaplan-Meier estimate was 82% at a median follow-up of six months.
• Funding reaches into 2029. Cash, cash equivalents and marketable debt securities were $555.7 million on 30 September 2026, per the third-quarter release of 4 November 2026. Xencor guides to $480 million to $500 million at the end of 2026.
• More cash is contracted. A final $52.5 million Alexion settlement payment is due in the third quarter of 2027, per the third-quarter release. Astellas's first Phase 3 dose of ASP2138 triggered a $25.0 million milestone.
• A partner drug using Xtend passed Phase 3. On 8 November 2026 Vir Biotechnology reported that 44% of 83 treated patients in ECLIPSE 1 reached undetectable hepatitis delta virus with normal liver enzymes at week 48, against 0% of 41 delayed-treatment patients. Tobevibart uses Xencor's Xtend half-life technology, and Vir plans a U.S. filing in mid-2027.
• Autoimmune programs show early activity. On 9 November 2026 Xencor reported that plamotamab cut the DAS28-ESR disease activity score by 3.3 points at week 12 on the two-dose regimen in rheumatoid arthritis, with B cells down more than 99%. In XmAb657's healthy-volunteer study, the median maximum B-cell reduction was 86% in the fifth dose cohort.
• The highest target sits well above the shares. Cantor Fitzgerald reiterated Overweight with a $70 target on 5 November 2026. MarketBeat listed an average target of $42.22 that day, in a range of $21 to $70.

Bear case

• The top-dose sample is 11 patients. The 95% confidence interval at 400 mcg/kg runs from 16.8% to 76.6%, so its lower end falls below the 25% bar. The study is single-arm and has no randomized comparator.
• Safety includes liver and immune effects. Grade 3 or higher treatment-related adverse events occurred in 72.1% of expansion patients in the 25 October 2026 data. These included raised AST (35.3%), raised ALT (33.8%) and rash (22.1%); grade 3 or higher cytokine release syndrome occurred in 5.9%.
• Dose-preparation errors cloud the comparison. On 25 October 2026 Xencor disclosed three suspected dose-preparation errors in the expansion cohorts. That makes the cohort-by-cohort results harder to read.
• The price sits at the near targets. The $38.13 close on 12 November 2026 is just under Canaccord Genuity's $40 target of 10 November 2026 and MarketBeat's $42.22 average of 5 November 2026.
• A director and the CFO sold after the rally. SEC Form 4 filings dated 12 November 2026 show director Richard Ranieri selling 81,252 shares at an average $39.25 on 10 November 2026 and CFO Bart Jan Cornelissen selling 10,100 shares at $39.82 on 11 November 2026. Both sales came within days of the 52-week high.
• Third-quarter revenue will not repeat cleanly. Revenue was $116.5 million against $21.0 million a year earlier, per the 10-Q filed 4 November 2026, and the release does not split royalty revenue by partner. Research and development expense was $84.3 million in the quarter.
• The plamotamab data are very early. Each of four dose cohorts held one to four patients as of 21 September 2026. One dose-level-4 patient stopped treatment after a serious adverse event the company judged unrelated, per the 9 November 2026 release.

Price setup

The shares closed at $34.05 on 5 November 2026, the session after the third-quarter report. They then closed at $35.75 on 6 November 2026, $38.59 on 9 November 2026, $39.39 on 10 November 2026 and $39.97 on 11 November 2026, each a new 52-week closing high. On 11 November 2026 they also traded as high as $40.60, the 52-week intraday high. The 12 November 2026 close of $38.13 is 6.1% below that high.

As of 12 November 2026 the 50-day moving average was $27.13 and the 200-day moving average $17.98. The last close sits far above both. The 52-week closing low was $10.41 on 19 May 2026, so the shares have more than tripled in six months.

The price already reflects the 25 October 2026 kidney-cancer data: the 12 November 2026 close of $38.13 sits just under Canaccord Genuity's $40 target and MarketBeat's $42.22 average target. The 50-day average is the nearest moving average below the shares. No quarterly report is due before late February 2027.

Catalysts ahead

• ~31 December 2026 (est.): Final single-dose XmAb657 healthy-volunteer cohort, expected by Xencor by year-end 2026. Shows whether higher doses deepen B-cell depletion beyond the 86% median seen in cohort 5 before patient dosing begins in the first quarter of 2027.
• ~31 December 2026 (est.): Blinded interim analysis of XmAb942 in the XENITH-UC ulcerative colitis study. Tests whether the study proceeds on plan ahead of a primary endpoint analysis expected in the second half of 2027.
• ~25 February 2027 (est.): Fourth-quarter 2026 report, estimated from the 25 February 2026 report a year earlier. Gives a clearer view of revenue after one-time third-quarter items and tests the $480 million to $500 million year-end cash guidance.
• 2027-Q1 (est.): Vir's ECLIPSE 2 and ECLIPSE 3 Phase 3 data for elebsiran plus tobevibart. Completes the package Vir plans to file in mid-2027 for a partner drug built on Xencor's Xtend technology.
• 2027-H1 (est.): More 400 mcg/kg XmAb819 results, subcutaneous dose-escalation results and FDA discussion of accelerated approval. Settles whether the 45.5% response rate seen in 11 patients holds in a larger group and whether a faster approval path exists.

What would change the view

A weekly close below $24.00, which would put the shares back near the $23.34 close of 14 August 2026 and erase the rise that followed the 25 October 2026 kidney-cancer data. A first-half 2027 confirmed response rate at 400 mcg/kg clearly below 25%, or an FDA view ruling out an accelerated path, would also break the case.

The risks this note tracks, each with what would confirm it:

• The 400 mcg/kg response rate falls once more patients are evaluated, because the first reading rests on 11 patients. Confirmed by: a confirmed response rate clearly below 25% at 400 mcg/kg when 20 or more patients are evaluable in the first half of 2027.
• Liver-enzyme elevations, rash or cytokine release syndrome force a lower dose or delay the pivotal study. Confirmed by: Xencor changes the proposed 400 mcg/kg dose, or grade 3 or higher transaminase events rise in later data cuts.
• The FDA does not support an accelerated-approval path on a single-arm study. Confirmed by: company disclosure after the first-half 2027 FDA discussion that a randomized trial is required before filing.
• Analysts see the kidney-cancer data as fully priced after the shares reached the near targets. Confirmed by: rating downgrades to neutral, or new targets set below the share price, from firms covering Xencor.
• Revenue drops after one-time third-quarter items while research spending keeps rising. Confirmed by: fourth-quarter 2026 revenue far below $116.5 million with research and development expense at or above the third quarter's $84.3 million.
• Xencor raises equity, or insider selling widens beyond the director and CFO sales of 10 November 2026 and 11 November 2026. Confirmed by: a prospectus supplement or at-the-market program in an SEC filing, or further director and officer sales in Form 4 filings.

What it trades with

Xencor trades mainly on its own clinical readouts, as the rise after the 25 October 2026 ESMO data shows. Its listed Oncology & immunology peers, Genmab, Replimune, Nanobiotix and Delcath, run separate programs with their own catalysts, so their moves are a weak guide to Xencor's. Vir Biotechnology's hepatitis delta program is a second link, because tobevibart carries Xencor's Xtend technology; Vir's ECLIPSE 2 and ECLIPSE 3 data, expected in early 2027, bear on that partner value. After a 63.4% three-month gain, the shares are also exposed to swings in small- and mid-cap biotech sentiment that have nothing to do with Xencor's data.