XBI · WMTMT

Aug 25, 2025Nov 21, 2025Feb 25, 2026May 27, 2026Aug 26, 2026

Breadth

126 / 147

stocks rose with the index

Concentration

11%

of the gain from MRNA, TWST, ERAS

Biggest driver

MRNA +4.61

MODERNA INC, +490.37%

Biggest drag

SMMT −1.75

SUMMIT THERAPEUTICS INC, −45.83%

What drove it

147 members · drivers first · 1Y · residual 772.6bp exceeds 60bp gate

The XBI rose 89.65% (+79.60 pts) over the past year in a broad advance: 126 of 147 stocks rose, with MRNA out front at +4.61 points.

Read the latest market-close note: A Flat Headline on the S&P 500 Masks a Split Between Goldman Sachs and Apple

+85.0 pts from 125 gainers−7.1 pts from 22 losers

net +79.6 pts · gainers outweigh losers 11.9 to 1

Stock

Points

Return

XBIsum of all 147 stocks

+79.6

+89.65%

MRNAMODERNA INC

+4.6

+490.37%

TWSTTWIST BIOSCIENCE CORP

+2.6

+452.83%

ERASERASCA INC

+1.9

+1,104.40%

ORKAORUKA THERAPEUTICS INC

+1.9

+585.32%

DNTHDIANTHUS THERAPEUTICS INC

+1.8

+373.13%

SYRESPYRE THERAPEUTICS INC

+1.8

+464.57%

APGEAPOGEE THERAPEUTICS INC

+1.8

+265.32%

CGONCG ONCOLOGY INC

+1.7

+208.50%

RLAYRELAY THERAPEUTICS INC

+1.6

+454.42%

RVMDREVOLUTION MEDICINES INC

+1.6

+503.98%

TVTXTRAVERE THERAPEUTICS INC

+1.5

+289.55%

KRYSKRYSTAL BIOTECH INC

+1.5

+145.12%

IMVTIMMUNOVANT INC

+1.4

+194.76%

PTGXPROTAGONIST THERAPEUTICS INC

+1.4

+166.35%

ARWRARROWHEAD PHARMACEUTICALS IN

+1.3

+330.32%

117 othersclick to expand the full index

+56.4

EBSEMERGENT BIOSOLUTIONS INC

−0.1

−35.22%

ORICORIC PHARMACEUTICALS INC

−0.1

+44.59%

VSTMVERASTEM INC

−0.1

−17.71%

MYGNMYRIAD GENETICS INC

−0.1

−47.03%

ADMAADMA BIOLOGICS INC

−0.1

−43.39%

SIONSIONNA THERAPEUTICS INC

−0.2

−74.36%

RXRXRECURSION PHARMACEUTICALS A

−0.2

−27.74%

INSMINSMED INC

−0.2

−3.06%

ARDXARDELYX INC

−0.3

−36.80%

SPRYARS PHARMACEUTICALS INC

−0.3

−55.37%

VORVOR BIOPHARMA INC

−0.3

−42.55%

MPLTMAPLIGHT THERAPEUTICS INC

−0.7

−29.88%

ALNYALNYLAM PHARMACEUTICALS INC

−0.9

−46.13%

CAPRCAPRICOR THERAPEUTICS INC

−1.4

+41.82%

SMMTSUMMIT THERAPEUTICS INC

−1.8

−45.83%

Cap weighting, illustrated

SCHOLAR ROCK HOLDING CORP and SAVARA INC moved almost identically (+80.14% vs +78.66%), yet SRRK moved the XBI 45.5× as much. In a cap-weighted index, the bigger company's weight turns the same percentage move into far more points.

Attribution map

slicing the +79.60 pt move · cell size = points contributed · color = direction, intensity = return

MRNA+4.6 pts(+490.4%)

TWST+2.6 pts(+452.8%)

ERAS+1.9 pts(+1,104.4%)

ORKA+1.9 pts(+585.3%)

DNTH+1.8 pts(+373.1%)

SYRE+1.8 pts(+464.6%)

APGE+1.8 pts

SMMT−1.8 pts

CGON+1.7 pts

RLAY

RVMD+1.6 pts(+504.0%)

TVTX+1.5 pts(+289.6%)

KRYS+1.5 pts

CAPR−1.4 pts

IMVT+1.4 pts

PTGX

ARWR+1.3 pts

ROIV+1.3 pts

SLS+1.3 pts

PRAX+1.3 pts

SRRK

BEAM

PCVX+1.2 pts

KYMR+1.2 pts

NTRA+1.2 pts

IBRX

DYN

CYTK

COGT

VRDN

REGN

TGTX

HALO

DNLI

PURR

GRAL

ALNY

IDYA

ZBIO+0.8 pts

BBIO+0.8 pts

AMGN

VKTX

TNGX+0.7 pts

PVLA+0.7 pts

TRAX

BIIB

MIRM

UTHR

INBX

VRTX

IONS

PTCT

CLDX

ABSI

QURE

AVTX

XNCR

ABBV

CGEM

KOD

MLYS

IRON

VIR

CRSP

ARQT

MDGL

VERA

NRIX

CRVS

Concentration curve

cumulative share of the +79.60 pt move · sorted by contribution

When they drove it

cumulative points through the period

Breadth

member returns, this period

−100%+100%+300%+500%+700%+900%+1,100%

From −74.36% (SION) to +1,104.40% (ERAS). Equal-weight, the XBI would be +151.25% vs the actual +89.65%; the gap is what cap weighting did.

By sector

point contribution · sums to +79.60 pts

-147

+77.8

The year, session by session

every trading day of 2026 · hover for the move

JANFEBMARAPRMAYJUNJULAUG

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SPDR S&P Biotech ETF

What drove it

Attribution map

Concentration curve

When they drove it

Breadth

By sector

The year, session by session

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